Experimental research studies on tools for extravehicular maintenance in space, phase 2 Final report

Space tool configurations for extravehicular maintenanc

Computational interferometric description of nested flow fields

Computer graphics and theoretical descriptions of density are used to obtain computer generated flow visualizations called computational interferograms. Computational interferograms are pictorially analogous to optical interferograms, and examples showing the fringe pattern for the flow about a sharp tip cone in a supersonic air stream are presented. To ascertain the effect of unsteady behavior, local density disturbances are added to the steady state flow field. This introduces irregularities to the computational interferogram like those seen in the optical interferograms. These theoretical disturbances can be varied in geometry, density description, translated with time, and strengthened or dissipated. The accuracy of computational interferometry relies on the accuracy of the theoretical density descriptions and therefore, it provides a way of verifying existing models of flow fields, especially those containing unsteady or turbulent behavior. In addition to being a unique method of flow visualization, computational interferometry can be used to develop and modify theories or numerical solutions to both simple and complex flow fields. The presented research is a general description of this process

Learning-Oriented Assessment: The Affective Dimension

As elucidated by Purpura and Turner in their presentation at the Teachers College Columbia University Round Table in Second Language Studies (TCCRISLS) 2014 conference, language-oriented assessment (LOA) emphasizes the centrality of learning when the interrelatedness between instruction, assessment, and learning are examined. The LOA framework is composed of seven dimensions: the contextual dimension, the elicitation dimension, the proficiency dimension, the learning dimension, the instructional dimension, the interactional dimension, and the affective dimension. This article will explore the affective dimension as it surfaced in the papers presented at the TCCRISLS conference

New Trends in Pragmatics Assessment Research: An Introduction

Even though it can be argued that pragmatics is an important element of the second language (L2) assessment research agenda, a number of challenges have consistently surfaced in this field. For example, adequate coverage of the construct has been consistently formidable, particularly considering that many studies take an atomistic view of pragmatics through their focus on speech acts rather than on contextualized language use (Roever, 2010). Likewise, issues of practicality and benchmarking remain underdeveloped, and understanding regarding the hierarchy of different types of pragmatic meanings continues to be limited (Roever, 2012, 2014). However, in recent years, there have been several attempts to expand our understanding of L2 pragmatics. As illustration, new models of pragmatic ability have been proposed (Purpura, 2017; Timpe-Laughlin, Wain, & Schmidgall, 2015), and it is hoped that these theoretical developments lead to practical applications in L2 pragmatics research and pedagogy

Defining, Conceptualizing, Problematizing, and Assessing Language Teacher Assessment Literacy

Assessment literacy (AL) empowers teachers (Grabowski & Dakin, 2014) by helping them make better decisions about the development, administration, and use of assessments (Harding & Kremmel, 2016; Popham, 2009). This is crucial because when teachers make erroneous interpretations, which lead to incorrect decisions, students can suffer unintended, negative consequences (Purpura, 2016; Purpura, Brown, & Schoonen, 2015). As essential as AL is to providing quality teaching and learning opportunities, assessment education remains inadequate (Lam, 2015; Mendoza & Arandia, 2009; Vogt & Tsagari, 2014). According to Cheng (2001), teachers spend up to a third of their time in assessment related activities; however, most “do so with little or no professional training” (Bachman, 2000, p. 19-20). In light of the demand for the development of instructor AL, this paper first defines and conceptualizes language assessment literacy (LAL). Then it problematizes LAL through an investigation of empirical studies conducted to explore pre- and in-service teacher education and resources that have been used to develop teachers’ LAL. Finally, it examines how teachers’ LAL levels are evaluated through assessments such as Cambridge University Press’s Teaching Knowledge Test, the edTPA, and state teacher certification Praxis tests

Optical-phonon resonances with saddle-point excitons in twisted-bilayer graphene

Twisted-bilayer graphene (tBLG) exhibits van Hove singularities in the density of states that can be tuned by changing the twisting angle $\theta$. A $\theta$-defined tBLG has been produced and characterized with optical reflectivity and resonance Raman scattering. The $\theta$-engineered optical response is shown to be consistent with persistent saddle-point excitons. Separate resonances with Stokes and anti-Stokes Raman scattering components can be achieved due to the sharpness of the two-dimensional saddle-point excitons, similar to what has been previously observed for one-dimensional carbon nanotubes. The excitation power dependence for the Stokes and anti-Stokes emissions indicate that the two processes are correlated and that they share the same phonon.Comment: 5 pages, 6 figure

An Interview with APPLE Lecture Speaker Professor Roy Lyster

On February 16, 2018, Working Papers in Applied Linguistics and TESOL (represented by Kaylee Fernandez, Michelle Stabler-Havener, and Carol HoiYee Lo) had the great pleasure of interviewing Dr. Roy Lyster, the invited speaker for the 2018 Applied Linguistics & Language Education (APPLE) Lecture Series hosted annually by the Applied Linguistics and TESOL Program at Teachers College, Columbia University. Dr. Lyster shared his research and advice he has for current and future researchers and educators in Applied Linguistics and TESOL. Dr. Roy Lyster is Emeritus Professor of Second Language Education in the Department of Integrated Studies Education at McGill University in Montreal, Canada. His research examines content-based language teaching and the effects of instructional interventions designed to counterbalance form-focused and content-based approaches. His research interests also include professional development and collaboration among teachers for the purpose of integrated language learning and biliteracy development. He was co-recipient with colleague Leila Ranta of the 1998 Paul Pimsleur Award for Research in Foreign Language Education and was presented the Robert Roy Award by the Canadian Association of Second Language Teachers in 2017. He was co-president then president of the Canadian Association of Applied Linguistics from 2004 to 2008. He is author of a module called Content-Based Language Teaching published by Routledge in 2018, and two books: Learning and Teaching Languages Through Content published by Benjamins in 2007 and Vers une approche intégrée en immersion published by Les Éditions CEC in 2016

An Interview with APPLE Lecture Speaker Dr. Richard Donato

On March 6, 2020, the Studies in Applied Linguistics and TESOL (SALT) journal had the great pleasure of interviewing Dr. Richard Donato, the invited speaker for the 2020 APPLE Lectures Series hosted by the Applied Linguistics and TESOL Program at Teachers College, Columbia University. Dr. Donato was kind enough to take the time, during a very busy day, to speak about his work on teacher training, history-in-person, and culture in the language classroo

Multi-omic profiling reveals the ataxia protein sacsin is required for integrin trafficking and synaptic organization

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a childhood-onset cerebellar ataxia caused by mutations in SACS, which encodes the protein sacsin. Cellular ARSACS phenotypes include mitochondrial dysfunction, intermediate filament disorganization, and progressive death of cerebellar Purkinje neurons. It is unclear why the loss of sacsin causes these deficits or why they manifest as cerebellar ataxia. Here, we perform multi-omic profiling in sacsin knockout (KO) cells and identify alterations in microtubule dynamics and mislocalization of focal adhesion (FA) proteins, including multiple integrins. Deficits in FA structure, signaling, and function can be rescued by targeting PTEN, a negative regulator of FA signaling. ARSACS mice possess mislocalization of ITGA1 in Purkinje neurons and synaptic disorganization in the deep cerebellar nucleus (DCN). The sacsin interactome reveals that sacsin regulates interactions between cytoskeletal and synaptic adhesion proteins. Our findings suggest that disrupted trafficking of synaptic adhesion proteins is a causal molecular deficit in ARSACS

Common and rare genetic markers of lipid variation in subjects with type 2 diabetes from the ACCORD clinical trial

Background Individuals with type 2 diabetes are at an increased risk of cardiovascular disease. Alterations in circulating lipid levels, total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides (TG) are heritable risk factors for cardiovascular disease. Here we conduct a genome-wide association study (GWAS) of common and rare variants to investigate associations with baseline lipid levels in 7,844 individuals with type 2 diabetes from the ACCORD clinical trial. Methods DNA extracted from stored blood samples from ACCORD participants were genotyped using the Affymetrix Axiom Biobank 1 Genotyping Array. After quality control and genotype imputation, association of common genetic variants (CV), defined as minor allele frequency (MAF) ≥ 3%, with baseline levels of TC, LDL, HDL, and TG was tested using a linear model. Rare variant (RV) associations (MAF < 3%) were conducted using a suite of methods that collapse multiple RV within individual genes. Results Many statistically significant CV ( p  < 1 × 10 −8 ) replicate findings in large meta-analyses in non-diabetic subjects. RV analyses also confirmed findings in other studies, whereas significant RV associations with CNOT2 , HPN-AS1 , and SIRPD appear to be novel ( q  < 0.1). Discussion Here we present findings for the largest GWAS of lipid levels in people with type 2 diabetes to date. We identified 17 statistically significant ( p  < 1 × 10 −8 ) associations of CV with lipid levels in 11 genes or chromosomal regions, all of which were previously identified in meta-analyses of mostly non-diabetic cohorts. We also identified 13 associations in 11 genes based on RV, several of which represent novel findings