Preservice Teacher Learning to Help English Language Learners Make Sense of Mathematics

This study investigates how preservice teachers (PST) help English language learners (ELLs) understand cognitive demanding mathematical problems using complicated language use. Three mathematics PSTs worked with ELLs in one-on-one settings while receiving individual interventions. The strategies they implemented were analyzed based on four categories: mathematical content, culture/life experience, mathematical/cognitive process, and mathematical/contextual language. As time evolved, all of the PSTs began to integrate life connection strategies and various visuals that are closely related to mathematical situations, which they learned during the interventions. This study suggests that PSTs require significant preparation infused with practical experiences and examples in order to design a linguistically and conceptually rich lesson

Preservice teacher learning for supporting English language learners to make sense of mathematics

This study examines how future mathematics teachers support English language learners (ELLs) when making sense of mathematical problems with complicated language use. In this study, three middle school mathematics prospective teachers, who enrolled in a university-based teacher preparation program, worked with ELLs in one-on-one settings while learning various ELL teaching strategies. The strategies they implemented when working with ELLs were analyzed through various sources such as written lesson plans, videotaped teaching practices, and written reflections. As time evolved, all of the teachers began to apply life-connection strategies and to integrate various visuals closely connected to mathematical situations into their lessons, which they learned during the interventions. They showed a positive influence from the interventions although their use of strategies were limited. This study suggest that mathematics teachers need to have significant preparation infused with practical experiences and examples in order to design a linguistically and conceptually rich lesson while making meaningful connections between mathematics and ELLs' experiences

Student-Centered Pedagogy: Using Moses’ Five-Step Approach as a Scaffolding Framework to Teach Diverse Learners

In this article, two teacher educators and three preservice teachers reflect on the critical role Moses’ Five-Step Approach (Moses & Cobb, 2001) played as a scaffolding pedagogical framework in preservice teacher and faculty learning. Using Moses’ approach to frame their presentations, preservice teachers work in their groups to teach abstract Educational Psychology concepts to actively engage classmates from diverse backgrounds. During this process, the presenters co-construct knowledge with their peers and instructor, applying the framework by putting common activities and everyday language first before teaching abstract concepts and academic language. The authors, including a preservice teacher who also teaches a university biology course, explicate the process of their experience, beginning with conceptualizing a theme, generating engaging activities that represent the concepts and tap into multimodalities of learning, and breaking down key vocabulary to connect to students’ prior knowledge in a socially constructed environment. The authors reflect on the power of this student-centered framework as well as its challenges. Ultimately, Moses’ approach serves as a liberating framework, allowing diverse learners a common entry point to experience and comprehend complex concepts and vocabulary. This pedagogical framework fosters a rich student-centered environment where students become active agents of their own learning

X-ray induced persistent photoconductivity in Si-doped Al0.35_{0.35}Ga0.65_{0.65}As

We demonstrate that X-ray irradiation can be used to induce an insulator-metal transition in Si-doped Al$_{0.35}$Ga$_{0.65}$As, a semiconductor with {\it DX} centers. The excitation mechanism of the {\it DX} centers into their shallow donor state was revealed by studying the photoconductance along with fluorescence. The photoconductance as a function of incident X-ray energy exhibits an edge both at the Ga and As K-edge, implying that core-hole excitation of Ga and As are efficient primary steps for the excitation of {\it DX} centers. A high quantum yield ($\gg 1$) suggests that the excitation is indirect and nonlocal, due to secondary electrons, holes, and fluorescence photons.Comment: 3 pages of text, 6 figures. An error in Fig.5 was detected, so we corrected i

Sub-Wavelength Terahertz Spin-Flip Laser Based on a Magnetic Point-Contact Array

We present a novel design for a single-mode, truly sub-wavelength THz disk laser based on a nano-composite gain medium comprising an array of metal/ferromagnetic point contacts embedded in a thin dielectric layer. Stimulated emission of light occurs in the point contacts as a result of spin-flip relaxation of spin-polarized electrons that are injected from the ferromagnetic side of the contacts. Ultra-high electrical current densities in the contacts and a dielectric material with a large refractive index, neither condition being achievable in conventional semiconductor media, allows the thresholds of lasing to be overcome for the lowest-order modes of the disk, hence making single-mode operation possible.Comment: 9 pages,4 figure

Personalized Three-Dimensional Printed Models in Congenital Heart Disease

Patient-specific three-dimensional (3D) printed models have been increasingly used in cardiology and cardiac surgery, in particular, showing great value in the domain of congenital heart disease (CHD). CHD is characterized by complex cardiac anomalies with disease variations between individuals; thus, it is difficult to obtain comprehensive spatial conceptualization of the cardiac structures based on the current imaging visualizations. 3D printed models derived from patient’s cardiac imaging data overcome this limitation by creating personalized 3D heart models, which not only improve spatial visualization, but also assist preoperative planning and simulation of cardiac procedures, serve as a useful tool in medical education and training, and improve doctor–patient communication. This review article provides an overall view of the clinical applications and usefulness of 3D printed models in CHD. Current limitations and future research directions of 3D printed heart models are highlighted