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  1. Abstract Background and Aims

    Transcriptome sequencing is a cost-effective approach that allows researchers to study a broad range of questions. However, to preserve RNA for transcriptome sequencing, tissue is often kept in special conditions, such as immediate ultracold freezing. Here, we demonstrate that RNA can be obtained from 6-month-old, field-collected samples stored in silica gel at room temperature. Using these transcriptomes, we explore the evolutionary relationships of the genus Pitcairnia (Bromeliaceae) in the Dominican Republic and infer barriers to gene flow.

    Methods

    We extracted RNA from silica-dried leaf tissue from 19 Pitcairnia individuals collected across the Dominican Republic. We used a series of macro- and micro-evolutionary approaches to examine the relationships and patterns of gene flow among individuals.

    Key Results

    We produced high-quality transcriptomes from silica-dried material and demonstrated that evolutionary relationships on the island match geography more closely than species delimitation methods. A population genetic examination indicates that a combination of ecological and geographical features presents barriers to gene flow in Pitcairnia.

    Conclusions

    Transcriptomes can be obtained from silica-preserved tissue. The genetic diversity among Pitcairnia populations does not warrant classification as separate species, but the Dominican Republic contains several barriers to gene flow, notably the Cordillera Central mountain range.

     
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  2. Determining the most appropriate method of scoring an assessment is basedon multiple factors, including the intended use of results, the assessment's pur-pose, and time constraints. Both the dichotomous and partial credit modelshave their advantages, yet direct comparisons of assessment outcomes fromeach method are not typical with constructed response items. The presentstudy compared the impact of both scoring methods on the internal structureand consequential validity of a middle-grades problem-solving assessmentcalled the problem solving measure for grade six (PSM6). After being scoredboth ways, Rasch dichotomous and partial credit analyses indicated similarlystrong psychometric findings across models. Student outcome measures on thePSM6, scored both dichotomously and with partial credit, demonstratedstrong, positive, significant correlation. Similar demographic patterns werenoted regardless of scoring method. Both scoring methods produced similarresults, suggesting that either would be appropriate to use with the PSM6. 
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  3. In the United States, national and state standardized assessments have become a metric for measuring student learning and high-quality learning environments. As the COVID- 19 pandemic offered a multitude of learning modalities (e.g., hybrid, socially distanced face-to-face instruction, virtual environment), it becomes critical to examine how this learning disruption influenced elementary mathematic performance. This study tested for differences in mathematics performance on fourth grade standardized tests before and during COVID-19 in a case study of a rural Ohio school district using the Measure of Academic Progress (MAP) mathematics test. A two-way ANOVA showed that fourth- grade MAP mathematics scores were statistically similar for the 2019 pre-COVID cohort (n = 31) and 2020 COVID-19 cohort (n = 82), and by gender group, between Fall 2019 and Fall 2020. Implications for rural students’ academic performance in virtual learning environments are discussed. 
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  4. The Delphi method has been adapted to inform item refinements in educational and psychological assessment development. An explanatory sequential mixed methods design using Delphi is a common approach to gain experts' insight into why items might have exhibited differential item functioning (DIF) for a sub-group, indicating potential item bias. Use of Delphi before quantitative field testing to screen for potential sources leading to item bias is lacking in the literature. An exploratory sequential design is illustrated as an additional approach using a Delphi technique in Phase I and Rasch DIF analyses in Phase II. We introduce the 2 × 2 Concordance Integration Typology as a systematic way to examine agreement and disagreement across the qualitative and quantitative findings using a concordance joint display table. A worked example from the development of the Problem-Solving Measures Grades 6–8 Computer Adaptive Tests supported using an exploratory sequential design to inform item refinement. The 2 × 2 Concordance Integration Typology (a) crystallized instances where additional refinements were potentially needed and (b) provided for evaluating the distribution of bias across the set of items as a whole. Implications are discussed for advancing data integration techniques and using mixed methods to improve instrument development. 
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  5. Determining the most appropriate method of scoring an assessment is based on multiple factors, including the intended use of results, the assessment's purpose, and time constraints. Both the dichotomous and partial credit models have their advantages, yet direct comparisons of assessment outcomes from each method are not typical with constructed response items. The present study compared the impact of both scoring methods on the internal structure and consequential validity of a middle-grades problem-solving assessment called the problem solving measure for grade six (PSM6). After being scored both ways, Rasch dichotomous and partial credit analyses indicated similarly strong psychometric findings across models. Student outcome measures on the PSM6, scored both dichotomously and with partial credit, demonstrated strong, positive, significant correlation. Similar demographic patterns were noted regardless of scoring method. Both scoring methods produced similar results, suggesting that either would be appropriate to use with the PSM6. 
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  6. Problem solving is a central focus of mathematics teaching and learning. If teachers are expected to support students' problem-solving development, then it reasons that teachers should also be able to solve problems aligned to grade level content standards. The purpose of this validation study is twofold: (1) to present evidence supporting the use of the Problem Solving Measures Grades 3–5 with preservice teachers (PSTs), and (2) to examine PSTs' abilities to solve problems aligned to grades 3–5 academic content standards. This study used Rasch measurement techniques to support psychometric analysis of the Problem Solving Measures when used with PSTs. Results indicate the Problem Solving Measures are appropriate for use with PSTs, and PSTs' performance on the Problem Solving Measures differed between first-year PSTs and end-of-program PSTs. Implications include program evaluation and the potential benefits of using K-12 student-level assessments as measures of PSTs' content knowledge. 
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  7. Lischka, A. ; Dyer, E. ; Jones, R. ; Lovett, J. ; Strayer, J. ; Drown, S. (Ed.)
    Using a test for a purpose it was not intended for can promote misleading results and interpretations, potentially leading to negative consequences from testing (AERA et al., 2014). For example, a mathematics test designed for use with grade 7 students is likely inappropriate for use with grade 3 students. There may be cases when a test can be used with a population related to the intended one; however, validity evidence and claims must be examined. We explored the use of student measures with preservice teachers (PSTs) in a teacher-education context. The present study intends to spark a discussion about using some student measures with teachers. The Problem-solving Measures (PSMs) were developed for use with grades 3-8 students. They measure students’ problem-solving performance within the context of the Common Core State Standards for Mathematics (CCSSI, 2010; see Bostic & Sondergeld, 2015; Bostic et al., 2017; Bostic et al., 2021). After their construction, the developers wondered: If students were expected to engage successfully on the PSMs, then might future grades 3-8 teachers also demonstrate proficiency? 
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  8. Lischka, A ; Dyer, E. ; Lovett, J. Strayer ; Drown, S. (Ed.)
    Using a test for a purpose it was not intended for can promote misleading results and interpretations, potentially leading to negative consequences from testing (AERA et al., 2014). For example, a mathematics test designed for use with grade 7 students is likely inappropriate for use with grade 3 students. There may be cases when a test can be used with a population related to the intended one; however, validity evidence and claims must be examined. We explored the use of student measures with preservice teachers (PSTs) in a teacher-education context. The present study intends to spark a discussion about using some student measures with teachers. The Problem-solving Measures (PSMs) were developed for use with grades 3-8 students. They measure students’ problem-solving performance within the context of the Common Core State Standards for Mathematics (CCSSI, 2010; see Bostic & Sondergeld, 2015; Bostic et al., 2017; Bostic et al., 2021). After their construction, the developers wondered: If students were expected to engage successfully on the PSMs, then might future grades 3-8 teachers also demonstrate proficiency? 
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  9. Lischka, A ; Dyer, E. ; Jones, E. ; Lovett, J. ; Strayer, J. ; Drown, S. (Ed.)
    Using a test for a purpose it was not intended for can promote misleading results and interpretations, potentially leading to negative consequences from testing (AERA et al., 2014). For example, a mathematics test designed for use with grade 7 students is likely inappropriate for use with grade 3 students. There may be cases when a test can be used with a population related to the intended one; however, validity evidence and claims must be examined. We explored the use of student measures with preservice teachers (PSTs) in a teacher-education context. The present study intends to spark a discussion about using some student measures with teachers. The Problem-solving Measures (PSMs) were developed for use with grades 3-8 students. They measure students’ problem-solving performance within the context of the Common Core State Standards for Mathematics (CCSSI, 2010; see Bostic & Sondergeld, 2015; Bostic et al., 2017; Bostic et al., 2021). After their construction, the developers wondered: If students were expected to engage successfully on the PSMs, then might future grades 3-8 teachers also demonstrate proficiency? 
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  10. Problem solving is central to mathematical work and is a core component of mathematical standards found in many instructional standards. As such, effective measures must be available to scholars and school personnel. Assessment is a key part of the teaching and learning process. Additionally, scholars need rigorous assessments with robust validity evidence to use results from those assessments as part of generalizable research. The focus of this paper is development of one problem solving measure for grade 5 (ages 10-12) students. It is a measure within the Problem-Solving Measure (PSM) series. Results from this study offer a quantitative instrument that can be used broadly. 
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