Learning Productive Mathematical Talk Moves Through Mix-Reality Simulation: The Case of Pre-service Elementary Teachers in a Hispanic Serving Institution

Teacher preparation programs require pre-service teachers to engage in field experiences that include participation in classrooms (Freeman, 2010). Mix-Reality Simulation (MRS) is a technological tool that can be implemented to provide pre-service teachers opportunities to develop pedagogical techniques such as providing feedback, conducting discussions, integrating technology with instruction while at the same time exploring different environments (Hixon & So, 2009). This paper presents preliminary results of a first-stage research in the implementation of a MRSs’ into an elementary teacher education program at a large Hispanic-Serving Institution. The purpose of the study was to determine whether differences existed between the groups in eliciting student’s mathematical understanding through the use of productive mathematical talk-moves (Chapin, O’Connor, & Anderson, 2009). Preliminary analysis show that the pre-service teachers exposed to MRS felt more confident in conducting formative assessment of students through questioning and clinical interviews, than their peers not exposed to the Intervention

Perceptions and Opinions of the Usability of Simulations in a Mathematics Methods Course for Elementary Pre-Service Teachers

The acceptance, implementation, and adoption of emerging technologies in teacher preparation programs has significantly evolved, and it is now seen as a tool that enhances teacher’s teaching skills particularly during the first years of the program. The use of new technologies like Mixed-Reality Simulations (MRSs) in the preparation of future teachers, provides them the opportunity of developing teaching skills in a safe environment. In this article, the researchers studied the perceptions and opinions of Elementary Pre-Service Mathematics Teachers (EPSMT) that were exposed to the use MRSs in a mathematics methods course. The research questions were: (1) What are the EPSMTs s’ perceptions toward the use of MRSs as part of their teacher preparation program? and (2) what are the opinions of the EPSMTs in regard to the benefits and usefulness of MRS to leverage their teaching skill in productive mathematical talk moves? Results of the study shows that EPSMTs perceive the use of MRSs as beneficial tool that effectively simulate classroom environments and students’ behaviors. The above is relevant since it facilitates the integration and adoption of state-of-the-art technologies like MRSs. Keywords: Pre-service Teachers, Mixed-Reality Simulations, Perceptions, Opinions. DOI: 10.7176/JEP/11-12-02 Publication date: April 30th 2020  

Mathematics Understanding of Elementary Pre-Service Teachers: The Analysis of their Procedural-Fluency, Conceptual-Understanding, and Problem-Solving Strategies

Students in an elementary teacher preparation program at a Hispanic Serving Institution in deep South Texas were asked to solve non-routine, problem-solving activities. They were administered five tasks during one semester, as part of a mathematics methods course. Two experienced raters assessed the student’s solutions to the non-routine problem-solving mathematical task using a mathematics understanding rubric that scores the Procedural Fluency (PF), Conceptual Understanding (CU), and Problem Solving/Strategic Competency (PS/SC). The research question was: What are the changes in procedural fluency, conceptual understanding, and problem solving-Strategic Competency in elementary preservice teachers after engaging in a series of non-routine problem-solving tasks? This is an ongoing research project, and preliminary results indicated that the teacher’s candidates made improvements in each of the three measurements, demonstrating that they are able to successfully use procedures, and have adequate conceptual knowledge for problem solving

Tyrosine dephosphorylation of H2AX modulates apoptosis and survival decisions.

Life and death fate decisions allow cells to avoid massive apoptotic death in response to genotoxic stress. Although the regulatory mechanisms and signalling pathways controlling DNA repair and apoptosis are well characterized, the precise molecular strategies that determine the ultimate choice of DNA repair and survival or apoptotic cell death remain incompletely understood. Here we report that a protein tyrosine phosphatase, EYA, is involved in promoting efficient DNA repair rather than apoptosis in response to genotoxic stress in mammalian embryonic kidney cells by executing a damage-signal-dependent dephosphorylation of an H2AX carboxy-terminal tyrosine phosphate (Y142). This post-translational modification determines the relative recruitment of either DNA repair or pro-apoptotic factors to the tail of serine phosphorylated histone H2AX (gamma-H2AX) and allows it to function as an active determinant of repair/survival versus apoptotic responses to DNA damage, revealing an additional phosphorylation-dependent mechanism that modulates survival/apoptotic decisions during mammalian organogenesis

Gene co-regulation by Fezf2 selects neurotransmitter identity and connectivity of corticospinal neurons

The neocortex contains an unparalleled diversity of neuronal subtypes, each defined by distinct traits that are developmentally acquired under the control of subtype-specific and pan-neuronal genes. The regulatory logic that orchestrates the expression of these unique combinations of genes is unknown for any class of cortical neuron. Here, we report that Fezf2 is a selector gene able to regulate the expression of gene sets that collectively define mouse corticospinal motor neurons (CSMN). We find that Fezf2 directly induces the glutamatergic identity of CSMN via activation of Vglut1 (Slc17a7) and inhibits a GABAergic fate by repressing transcription of Gad1. In addition, we identify the axon guidance receptor EphB1 as a target of Fezf2 necessary to execute the ipsilateral extension of the corticospinal tract. Our data indicate that co-regulated expression of neuron subtype–specific and pan-neuronal gene batteries by a single transcription factor is one component of the regulatory logic responsible for the establishment of CSMN identity

FE65 Binds Teashirt, Inhibiting Expression of the Primate-Specific Caspase-4

The Alzheimer disease (AD) amyloid protein precursor (APP) can bind the FE65 adaptor protein and this complex can regulate gene expression. We carried out yeast two-hybrid studies with a PTB domain of FE65, focusing on those genes that might be involved in nuclear signaling, and identified and validated Teashirt proteins as FE65 interacting proteins in neurons. Using reporter systems, we observed that FE65 could simultaneously recruit SET, a component of the inhibitor of acetyl transferase, and Teashirt, which in turn recruited histone deacetylases, to produce a powerful gene-silencing complex. We screened stable cell lines with a macroarray focusing on AD-related genes and identified CASP4, encoding caspase-4, as a target of this silencing complex. Chromatin immunoprecipitation showed a direct interaction of FE65 and Teashirt3 with the promoter region of CASP4. Expression studies in postmortem samples demonstrated decreasing expression of Teashirt and increasing expression of caspase-4 with progressive cognitive decline. Importantly, there were significant increases in caspase-4 expression associated with even the earliest neuritic plaque changes in AD. We evaluated a case-control cohort and observed evidence for a genetic association between the Teashirt genes TSHZ1 and TSHZ3 and AD, with the TSHZ3 SNP genotype correlating with expression of Teashirt3. The results were consistent with a model in which reduced expression of Teashirt3, mediated by genetic or other causes, increases caspase-4 expression, leading to progression of AD. Thus the cell biological, gene expression and genetic data support a role for Teashirt/caspase-4 in AD biology. As caspase-4 shows evidence of being a primate-specific gene, current models of AD and other neurodegenerative conditions may be incomplete because of the absence of this gene in the murine genome

Cirrhotic human liver extracellular matrix 3D scaffolds promote smad-dependent TGF-β1 epithelial mesenchymal transition

An altered liver microenvironment characterized by a dysregulated extracellular matrix (ECM) supports the development and progression of hepatocellular carcinoma (HCC). The development of experimental platforms able to reproduce these physio-pathological conditions is essential in order to identify and validate new therapeutic targets for HCC. The aim of this work was to validate a new in vitro model based on engineering three-dimensional (3D) healthy and cirrhotic human liver scaffolds with HCC cells recreating the micro-environmental features favoring HCC. Healthy and cirrhotic human livers ECM scaffolds were developed using a high shear stress oscillation-decellularization procedure. The scaffolds bio-physical/bio-chemical properties were analyzed by qualitative and quantitative approaches. Cirrhotic 3D scaffolds were characterized by biomechanical properties and microarchitecture typical of the native cirrhotic tissue. Proteomic analysis was employed on decellularized 3D scaffolds and showed specific enriched proteins in cirrhotic ECM in comparison to healthy ECM proteins. Cell repopulation of cirrhotic scaffolds highlighted a unique up-regulation in genes related to epithelial to mesenchymal transition (EMT) and TGFβ signaling. This was also supported by the presence and release of higher concentration of endogenous TGFβ1 in cirrhotic scaffolds in comparison to healthy scaffolds. Fibronectin secretion was significantly upregulated in cells grown in cirrhotic scaffolds in comparison to cells engrafted in healthy scaffolds. TGFβ1 induced the phosphorylation of canonical proteins Smad2/3, which was ECM scaffold-dependent. Important, TGFβ1-induced phosphorylation of Smad2/3 was significantly reduced and ECM scaffold-independent when pre/simultaneously treated with the TGFβ-R1 kinase inhibitor Galunisertib. In conclusion, the inherent features of cirrhotic human liver ECM micro-environment were dissected and characterized for the first time as key pro-carcinogenic components in HCC development