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Rough Draft Math for Engaged Learning
No full textThis article was originally published in Journal of Mathematics Education Leadership. The version of record is available at: https://scholarsjunction.msstate.edu/coe-publications/99/.Mathematics educators often face the challenge of students disliking mathematics or experiencing a negative relationship with the subject. Intentional teaching practices can be a mechanism to mitigate this challenge; thus, preservice and novice teachers would benefit from opportunities to develop such teaching practices. This research explored the potential of rough draft math (RDM) to support teachers in addressing these issues. RDM is a pedagogical approach where students discuss and share their preliminary mathematical ideas without the fear of being wrong. Teachers welcome rough draft thinking, which gives students explicit opportunities to review their work or thinking. This study examined the impact of RDM on preservice and novice secondary mathematics teachers through their written reflections on opportunities to learn about the approach through readings. Findings suggested that the readings can promote preservice and novice teachers' awareness of how RDM can foster a more comfortable and engaging learning environment, highlighting the importance of teachers holding a nonevaluative stance toward students' thinking and teachers' roles in facilitating mathematical discourse
Middle school students' algebraic lettering through an enactive theory of cognition
No full textJansen, AmandaWithin algebra education, students’ conceptions of “variables” (or letters applied with mathematical purpose, such as x in the expression 2x+3) have been a frequent topic of inquiry (e.g., Ellis & Özgür, 2024; Kieran, 2006; Küchemann, 1978; Trigueros & Jacobs, 2008). In this dissertation, I show how an alternative epistemological perspective on students’ activity--an enactive theory of cognition--can refocus inquiry on algebraic lettering, a term I introduce to refer to the generating of letters in the context of their algebra (e.g., writing x or saying y). Across two papers, I apply case study methodology to 1) examine the key features of three middle school students’ lettering processes over time (Chapter 2, “Identifying and Characterizing Algebraic Lettering in Middle-School Student Activity”) and 2) explore how it developed through students’ classroom interactions (Chapter 3, “The Emergence of Lettering in Classroom Interactions”). ☐ In my first paper, I investigate: What did three middle-school students learn with respect to lettering by the conclusion of an instructional unit in their classroom? I frame this inquiry as a multiple case study of the three students, drawing data from two task-based interviews conducted at the beginning and end of a unit of instruction about linear equations they experienced together. I applied qualitative techniques to construct cross-case data displays to compare and contrast the role of lettering across students and time points. I found that the students learned to letter in Process-Oriented, Representationally Connective, and Strategically Connective ways. I discuss implications for researchers and practitioners in designing tasks that can support future students’ emergent lettering processes in algebra. ☐ In my second paper, I explore the research question: How did students’ lettering emerge in classroom interactions during an instructional unit about linear equations? I investigated the three students’ activity as a collaborative group through five video-recorded classroom observations during their linear equations unit. Drawing from enactivism, I developed a technique called monologic centering analysis to examine the interdependent lettering trajectories of the students. Related to the three aforementioned features of lettering, I found that students’ lettering emerged within their classroom negotiations as they coordinated their lettering to achieve group goals and draw connections across representations and strategies in their work. I also found that the students drew upon five central environmental resources within these interactions—what tasks, the teacher, and groupmates said/wrote with respect to lettering, as well as lettering applied across representations of the same/different situations. I discuss how students’ development of algebraic literacy in classrooms can be supported as a result of these findings.University of Delaware, School of EducationPh.D
Inferring dysregulated kinases using kinase-substrate predictions of a machine learning model
No full textWu, Cathy H.Protein phosphorylation is a crucial post-translational modification that regulates many signaling pathways and cellular processes. It involves transfer of a phosphate group to specific amino acid residues of substrate proteins. Protein kinases are enzymes that catalyze phosphorylation. Often, when kinases are dysregulated, they trigger abnormal phosphorylation, which alters normal functioning of its substrates. In many human diseases, substrates are abnormally phosphorylated, and it is associated with aberrant kinase activity. ☐ Kinase activity inference methods identify differentially activated upstream kinases from observed differences in phosphorylation abundance of substrates. Typically, kinase activity inference techniques rely on the knowledge of kinase-substrate associations. However, experimentally validated kinase-substrate data is limited and includes less than 7% of human phosphorylation sites. In the last two decades, many tools have been developed to determine kinases of substrates. Most tools are limited by factors such as relying solely on sequence information around phosphorylation sites, offering limited coverage of human kinases, and lacking functional context in their predictions. Hence, in this dissertation, I use machine learning and knowledge graph embedding to predict kinases of human substrates by including functional context of proteins. ☐ Further, I evaluate the applicability of my model’s predictions in kinase activity inference using a kinase perturbation dataset. Finally, I apply my predictions to infer implicated kinases in tumor conditions and validate the results using signatures of cells with kinase-targeted drugs.University of Delaware, Center for Bioinformatics and Computational BiologyPh.D
Characterizing potential targets and inhibitors of the metalloproteinase ADAM9
No full textenterADAM9 (A Disintegrin and Metalloproteinase 9) is a transmembrane protein
with a metalloproteinase domain responsible for substrate ectodomain shedding, a
process crucial for cell adhesion and signaling. Dysregulation of ADAM9 is linked to
inflammation, neurodegenerative diseases, cancer metastasis, and autoimmunity. The
Wei lab pioneered a multi-omics approach to identify ADAM9 substrates and targets
through RNA sequencing and proteomics, revealing changes in secretion of exosome
markers CD9, CD63, and CD81 upon knockdown of ADAM9. Investigations into
these hits showed differential secretion into condition media of CD9 and CD63, but
not CD81. The Wei lab also screened small-molecule inhibitors and activators of
ADAM9 using a medium throughput drug screen, which identified promising
inhibitors of ADAM9, however these inhibitors had yet to be tested in cell-culture
based models. The inhibition of ADAM9 via Compound 6 has been evaluated by
Western blot detection of ADAM9 substrates identified by the Wei lab, IL10RB and
ephrin-B1. Building on these findings, this research project aimed to investigate the
role of ADAM9 in exosome release and further evaluate the potential of small molecule inhibitors of ADAM9. We found that following ADAM9 knockdown,
secretion of CD9, CD63, and CD81 varied unexpectedly suggesting that ADAM9 may
regulate exosome release through unexpected or compensatory mechanisms.
Treatment with Compound 6 showed varying effects on ADAM9 activity indicating
the need for further optimization of western blot conditions and additional validation
experiments to confirm Compound 6’s inhibition of ADAM9.ente
The impact of ESG on hotel corporate reputation: the moderating role of casino operation
No full textKim, Hong SoonDespite the ample empirical evidence on the ESG-firm outcome relationship, the implication of ESG on reputation, specifically in the hospitality industry, remains underexplored to date. Therefore, this study examined the ESG-corporate reputation relationship with moderating effect of casino operation. Drawing on Signaling and Legitimacy theories, this study addressed the current research by applying a linear regression with panel data drawn from the Thomson Reuters Refinitiv and Compustat database to analyze data on 24 public hotel firms in the United States between 2002 and 2023. Specifically, the result reveals that: environmental performance decreases corporate reputation, social performance has no significant effect on corporate reputation, while governance performance increases corporate reputation. In terms of the moderating effect, this study found that: casino operation positively moderates the environmental performance-corporate reputation relationship while negatively moderating both social performance-corporate reputation and governance performance-corporate reputation relationships. Theoretically, this study extends ESG -corporate reputation literature by providing a logical discussion about how each dimension of ESG is related to building a strong corporate reputation. In addition, this study advances the ESG studies in the field of hospitality management by introducing casino operations as a moderator factor, highlighting how industry-specific characteristics shape the ESG-corporate reputation relationship. Practically, this study provides insightful implications for industry practitioners in comprehending the individualized effect of ESG on corporate reputation.University of Delaware, Department of Hospitality and Sport Business ManagementM.S
Whole Exome Sequencing Study Uncovers Novel Candidate Genes and Protein-Coding Variants for Cataract
No full textThis article was originally published in Investigative Ophthalmology & Visual Science. The version of record is available at https://doi.org/10.1167/iovs.66.11.32
Copyright 2025 The Authors iovs.arvojournals.org
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.Purpose: To identify novel candidates for cataract and evaluate the contribution of protein-coding variants to cataract susceptibility.
Methods: We first leveraged a publicly-available browser, Genebass, to extract significant gene-based and single-variant association results for cataract in UK Biobank exomes (30,550 cataract cases and 364,291 controls). We then validated findings using genome-wide association study (GWAS) summary statistics from the Genetic Epidemiology Research in Adult Health and Aging (GERA) cohort (28,092 cataract cases and 50,487 controls). Finally, we examined the expression of the prioritized genes in lens tissue using the iSyTE database.
Results: Gene-based association testing identified four genes (KDM5B, COL2A1, MIP and CRYBB2) that were associated with cataract (P < 2.50 × 10−6), of which one (KDM5B) was neither previously reported to be associated with congenital cataract nor reported in GWAS. Single-variant association testing identified seven variants within six genes (BFSP2, ZNF800, MIP, HERC2, TSPAN10 and CPAMD8) that were associated with cataract (P < 1.00 × 10−8). Among the identified cataract variants, we found four missense, one synonymous, one frameshift, and one stop-gained variant. Associations at COL2A1, HERC2, and ZNF800 were validated in GERA. Importantly, majority of prioritized cataract genes were robustly expressed in iSyTE lens data and were enriched in structural constituent of eye lens, lens development in camera-type eye, visual perception, and collagen type II trimer pathways.
Conclusions: Our results demonstrate the value of gene-based and single-variant association testing for understanding cataract etiology and uncovering novel genetic risk factors. Our findings also show that cataract-associated genes are significantly expressed in lens tissues and lens-related biological pathways.The authors thank the KPNC members who have generously participated in the KP Research Program on Genes, Environment, and Health (RPGEH).
Participant enrollment, survey completion and biospecimen collection in RPGEH was supported by the Robert Wood Johnson Foundation, the Wayne and Gladys Valley Foundation, the Ellison Medical Foundation and the KP Community Benefit Programs. Genotyping of the GERA cohort was supported by grants from the National Institute on Aging, National Institute of Mental Health, and National Institute of Health Common Fund (RC2 AG036607). This work was funded by a grant from the National Eye Institute (R01 EY033010 to HC and SAL)
Mechanism of Anomalous Anisotropic Colossal Magnetoresistance in Quasi-2D Mn3Si2Te6 Bulk Single Crystal
No full textThis article was originally published in Advanced Science. The version of record is available at: https://doi.org/10.1002/advs.202514651
© 2025 The Author(s). Advanced Science published by Wiley-VCHGmbH. This is an open access article under the terms of the Creative Commons Attribution License, https://creativecommons.org/licenses/by/4.0/ which permits use, distribution and reproduction in any medium, provided the original work is properly cited.Mn3Si2Te6, quasi-2D ferrimagnetic semiconductor, exhibits anomalous saturated colossal magnetoresistance (CMR) only when a magnetic field is applied along its magnetic hard magnetization axis, suggesting unconventional underlying physics and promising potential for spintronic applications. However, the intrinsic mechanism behind this anomalous anisotropic CMR remain unresolved. In this work, the temperature and angular dependencies of magnetoresistance (MR) in high-quality Mn3Si2Te6 single crystals are systematically investigated. The MR measured within the easy ab-plane shows no saturation, whereas a large negative saturation MR of ≈ −100% is observed along the hard magnetization c-axis below the Curie temperature. To explain this behavior, a novel model is proposed in which in-plane magnetic fields induce quasi-2D magnetotransport, while out-of-plane fields promote a transition to 3D transport. Notably, when the c-axis field exceeds the demagnetizing field, the alignment between spin-polarized carriers and magnetic moments significantly suppresses scattering. The results challenge the applicability of the chiral orbital currents (COC) model in Mn3Si2Te6 single crystals and establish a new framework for controlling the CMR effect in layered magnets, offering a pathway toward future spintronic technologies.S.L., X.H., and S.L. contributed equally to this work. This work was sup-ported in part by the National Natural Science Foundation of China (GrantNos. 12274258, 12504059), the Natural Science Foundation of HubeiProvince (Grant Nos. 2024AFB333, 2024AFB289), and the Natural ScienceFoundation of Yichang (Grant No. A24-3-021
"Prophetic pins": sentiment and sensation in layette pincushions, 1760-1840
No full textBrückner, MartinVan Horn, JenniferIn the late-eighteenth and early-nineteenth centuries, layette pincushions were a common gift for expectant mothers either during pregnancy or just after the birth of the child. Created by a family member, friend, or neighbor, they would often be included as part of a layette set which is a collection of clothing and other items needed for the care of a newborn baby. Pins were heavily used by women in the eighteenth century for pinning babies’ diapers, headgear, clothing, and swaddling. These objects were typically marked with the initials and birth date of the child and included phrases such as “Welcome Little Stranger” and “God Bless the Babe and May It Live.” These words took on anticipatory and contingent significance as they would often be created before the birth of the child and would entirely shift in meaning if either the mother or the child did not survive the birth, which was a common occurrence during this era. As the messages and motifs are formed using the exposed pin heads as a design element, the aesthetic and sentimental value must be sacrificed by removing the pins to use them as fasteners. ☐ The practice of materially marking initials and dates on domestic textile objects is rooted in the needlework practices that women would have learned at an early age, beginning with embroidery samplers. Layette pincushions exemplify the material skills and moral values that early needlework education instilled in women as well as directly representing the significance of their assigned roles as mothers. Throughout women’s history the needle has been portrayed as both an instrument of suffering and reclamation as it represents the history of women’s oppression but also their ability to transcend these prescribed roles and gain a greater degree of autonomy. Directly related to the needle, the pin also contains a multitude of dualistic qualities. Opposed to the notions of care intended by these objects, layette pincushions also retain an inherent quality of violence. In addition to their ability to join or mend, pins can also cause pain, which was unfortunately a common occurrence for babies getting stuck with their own diaper pins prior to the invention of safety pins in 1849. ☐ Due to their unique materiality and distinct function, layette pincushions are valuable historical repositories of eighteenth-century craft, culture, and maternal identity. Women in the eighteenth century continuously crafted textile objects by hand that are imbued with sentimental value and continue to serve as mnemonic devices to fill the absence of loss. Existing at the intersection of material culture, the history of emotions, sensory history, and women’s history, this thesis seeks to draw out the relationships between the sensory experience and sentimental emotion of materially marking familial relationships with the shifting temporalities of anticipatory, commemorative, and memorial objects.M.A.University of Delaware, Winterthur Program in American Material Cultur