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BACKGROUND: Exposure to phthalates during the pubertal window impacts chronic disease risk and temporal trends in exposure can inform public health initiatives. OBJECTIVE: Characterize temporal trends in phthalate metabolite exposure for adolescent girls overall and by sociodemographic characteristics. METHODS: We used the cross-sectional data from each cycle of the National Health and Nutrition Examination Survey from years 2001 to 2018. We restricted participants to ages of 8-14 with at least one urinary measurement of the selected 12 phthalate metabolites within the study period (n=2,063). We used multivariable linear regression to assess temporal trends for selected individual phthalate metabolite concentrations (ng/ml) and source groupings of parent metabolites (sum low and high molecular weight phthalates; ∑LMW and ∑HMW) overall and individually by sociodemographic characteristics (race/ethnicity), nativity, socioeconomic status (SES), intersection of race/ethnicity-SES) to assess for modification. RESULTS: Overall ∑HMW and ∑LMW concentrations declined between 2001 and 2018; however, only ∑LMW consistently differed by all sociodemographic characteristics. Trends in ∑LMW concentration were significantly higher across all racial/ethnic groups, ranging from an average of 35% (Other Hispanic) to 65% (Mexican American and non-Hispanic Black) higher than non-Hispanic White (all p-values<0.0001). Compared to non-Hispanic White, we observed an average decrease of 15% in MiBP for non-Hispanic Black (ßSpline=-0.16, p<0.0001) and 28% for Other Hispanic (ßSpline=-0.33, p=0.01) in 2011-2018 vs. 2001-2010. Summary and individual LMW metabolite phthalate concentrations were 11%-49% higher among low vs. high SES girls. LMW metabolites MBP and MiBP were on average 22% and 35% higher; respectively, among foreign born vs. U.S. born. Compared to non-Hispanic Whites, all racial/ethnic groups had statistically significant higher trends in ∑LMW concentration irrespective of SES status. SIGNIFICANCE: Girls identifying with a historically disadvantaged racial/ethnic group have elevated ∑LMW concentrations irrespective of SES class; suggesting the need for interventions to mitigate exposure among the most historically disadvantaged strata.
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Field courses provide transformative learning experiences that support success and improve persistence for science, technology, engineering, and mathematics majors. But field courses have not increased proportionally with the number of students in the natural sciences. We conducted a scoping review to investigate the factors influencing undergraduate participation in and the outcomes from field courses in the United States. Our search yielded 61 articles, from which we classified the knowledge, affect, behavior, and skill-based outcomes resulting from field course participation. We found consistent reporting on course design but little reporting on demographics, which limits our understanding of who takes field courses. Cost was the most commonly reported barrier to student participation, and knowledge gains were the most commonly reported outcome. This scoping review underscores the need for more rigorous and evidence-based investigations of student outcomes in field courses. Understanding how field courses support or hinder student engagement is necessary to make them more accessible to all students.
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We describe the development of a new, freely available, online, programmatic-level assessment tool, Measuring Achievement and Progress in Science in Physiology, or Phys-MAPS ( http://cperl.lassp.cornell.edu/bio-maps ). Aligned with the conceptual frameworks of Core Principles of Physiology, and Vision and Change Core Concepts, Phys-MAPS can be used to evaluate student learning of core physiology concepts at multiple time points in an undergraduate physiology program, providing a valuable longitudinal tool to gain insight into student thinking and aid in the data-driven reform of physiology curricula. Phys-MAPS questions have a modified multiple true/false design and were developed using an iterative process, including student interviews and physiology expert review to verify scientific accuracy, appropriateness for physiology majors, and clarity. The final version of Phys-MAPS was tested with 2,600 students across 13 universities, has evidence of reliability, and has no significant statement biases. Over 90% of the physiology experts surveyed agreed that each Phys-MAPS statement was scientifically accurate and relevant to a physiology major. When testing each statement for bias, differential item functioning analysis demonstrated only a small effect size (<0.008) of any tested demographic variable. Regarding student performance, Phys-MAPS can also distinguish between lower and upper division students, both across different institutions (average overall scores increase with each level of class standing; two-way ANOVA, P < 0.001) and within each of three sample institutions (each ANOVA, P ≤ 0.001). Furthermore, at the level of individual concepts, only evolution and homeostasis do not demonstrate the typical increase across class standing, suggesting these concepts likely present consistent conceptual challenges for physiology students.
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Instrucción por Computador/normas , Evaluación Educacional/normas , Fisiología/educación , Estudiantes , Universidades/normas , Instrucción por Computador/métodos , Evaluación Educacional/métodos , Femenino , Humanos , MasculinoRESUMEN
To test the hypothesis that lecturing maximizes learning and course performance, we metaanalyzed 225 studies that reported data on examination scores or failure rates when comparing student performance in undergraduate science, technology, engineering, and mathematics (STEM) courses under traditional lecturing versus active learning. The effect sizes indicate that on average, student performance on examinations and concept inventories increased by 0.47 SDs under active learning (n = 158 studies), and that the odds ratio for failing was 1.95 under traditional lecturing (n = 67 studies). These results indicate that average examination scores improved by about 6% in active learning sections, and that students in classes with traditional lecturing were 1.5 times more likely to fail than were students in classes with active learning. Heterogeneity analyses indicated that both results hold across the STEM disciplines, that active learning increases scores on concept inventories more than on course examinations, and that active learning appears effective across all class sizes--although the greatest effects are in small (n ≤ 50) classes. Trim and fill analyses and fail-safe n calculations suggest that the results are not due to publication bias. The results also appear robust to variation in the methodological rigor of the included studies, based on the quality of controls over student quality and instructor identity. This is the largest and most comprehensive metaanalysis of undergraduate STEM education published to date. The results raise questions about the continued use of traditional lecturing as a control in research studies, and support active learning as the preferred, empirically validated teaching practice in regular classrooms.
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Logro , Ingeniería/educación , Matemática/educación , Aprendizaje Basado en Problemas/métodos , Ciencia/educación , Estudiantes/estadística & datos numéricos , Comprensión , Humanos , Competencia Mental , Metaanálisis como Asunto , Tecnología/educación , UniversidadesRESUMEN
In undergraduate life sciences education, open educational resources (OERs) increase accessibility and retention for students, reduce costs, and save instructors time and effort. Despite increasing awareness and utilization of these resources, OERs are not centrally located, and many undergraduate instructors describe challenges in locating relevant materials for use in their classes. To address this challenge, we have designed a resource collection (referred to as Open Resources for Biology Education, ORBE) with 89 unique resources that are primarily relevant to undergraduate life sciences education. To identify the resources in ORBE, we asked undergraduate life sciences instructors to list what OERs they use in their teaching and curated their responses. Here, we summarize the contents of the ORBE and describe how educators can use this resource as a tool to identify suitable materials to use in their classroom context. By highlighting the breadth of unique resources openly available for undergraduate biology education, we intend for the ORBE to increase instructors' awareness and use of OERs.
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Critical thinking, which can be defined as the evidence-based ways in which people decide what to trust and what to do, is an important competency included in many undergraduate science, technology, engineering, and mathematics (STEM) courses. To help instructors effectively measure critical thinking, we developed the Biology Lab Inventory of Critical Thinking in Ecology (Eco-BLIC), a freely available, closed-response assessment of undergraduate students' critical thinking in ecology. The Eco-BLIC includes ecology-based experimental scenarios followed by questions that measure how students decide on what to trust and what to do next. Here, we present the development of the Eco-BLIC using tests of validity and reliability. Using student responses to questions and think-aloud interviews, we demonstrate the effectiveness of the Eco-BLIC at measuring students' critical thinking skills. We find that while students generally think like experts while evaluating what to trust, students' responses are less expert-like when deciding on what to do next.
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In the microbial world, cell size and shape impact physiology, but students struggle to visualize spatial relationships between cells and macromolecules. In prokaryotic cells, cell size is limited by reliance on diffusion for nutrient uptake and the transport of nutrients within the cell. Cells must also meet a minimum size threshold to accommodate essential cellular components such as ribosomes and DNA. Using 3D printing allows for the creation of custom models that can be influential teaching tools in the biology classroom. This lesson uses 3D cell models to teach students enrolled in an introductory microbiology course about bacterial cell size and the biological importance of surface-area-to-volume ratio. During the lesson, students interact with 3D cell models and discuss a series of questions in small groups. Student learning was assessed using quantitative and qualitative student response data collected pre- and post-lesson. Student achievement of learning objectives, and their confidence in their knowledge of these concepts, improved post-lesson, and these gains were statistically significant. Our findings suggest that interacting with 3D-printed cell models improves student understanding about bacterial cell size and diffusion.
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An understanding of both cognitive and affective domains of learning is critical to promoting undergraduate student success in biology. Field courses-which support student learning, observation, and experimentation in the outdoors-have been shown to be effective in supporting cognitive student outcomes. However, less is known about students' affective responses during field instruction. To better understand the affective domain in this course type, we asked students enrolled in a campus-based introductory field biology course to engage in weekly reflective journaling over the course of a semester. We employed inductive and deductive coding of over 700 field journal reflections using the Model of the Affective Domain for the Geosciences as a conceptual basis. Informed by our results, we present a theoretically-driven, five-part Framework of Student Affect in Field Biology and in-depth and novel insights into what students feel, believe, and value as they participate in an undergraduate field course. Our framework and coding results can be used by field course instructors to understand how to better design experiences that leave students feeling confident in their abilities, interested to learn more about nature, and empowered to persist in the discipline.
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Critical thinking is the process by which people make decisions about what to trust and what to do. Many undergraduate courses, such as those in biology and physics, include critical thinking as an important learning goal. Assessing critical thinking, however, is non-trivial, with mixed recommendations for how to assess critical thinking as part of instruction. Here we evaluate the efficacy of assessment questions to probe students' critical thinking skills in the context of biology and physics. We use two research-based standardized critical thinking instruments known as the Biology Lab Inventory of Critical Thinking in Ecology (Eco-BLIC) and Physics Lab Inventory of Critical Thinking (PLIC). These instruments provide experimental scenarios and pose questions asking students to evaluate what to trust and what to do regarding the quality of experimental designs and data. Using more than 3000 student responses from over 20 institutions, we sought to understand what features of the assessment questions elicit student critical thinking. Specifically, we investigated (a) how students critically evaluate aspects of research studies in biology and physics when they are individually evaluating one study at a time versus comparing and contrasting two and (b) whether individual evaluation questions are needed to encourage students to engage in critical thinking when comparing and contrasting. We found that students are more critical when making comparisons between two studies than when evaluating each study individually. Also, compare-and-contrast questions are sufficient for eliciting critical thinking, with students providing similar answers regardless of if the individual evaluation questions are included. This research offers new insight on the types of assessment questions that elicit critical thinking at the introductory undergraduate level; specifically, we recommend instructors incorporate more compare-and-contrast questions related to experimental design in their courses and assessments.
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Estudiantes , Pensamiento , Humanos , Aprendizaje , FísicaRESUMEN
Undergraduate genetics courses have historically focused on simple genetic models, rather than taking a more multifactorial approach where students explore how traits are influenced by a combination of genes, the environment, and gene-by-environment interactions. While a focus on simple genetic models can provide straightforward examples to promote student learning, they do not match the current scientific understanding and can result in deterministic thinking among students. In addition, undergraduates are often interested in complex human traits that are influenced by the environment, and national curriculum standards include learning objectives that focus on multifactorial concepts. This research aims to discover to what extent multifactorial genetics is currently being assessed in undergraduate genetics courses. To address this, we analyzed over 1,000 assessment questions from a commonly used undergraduate genetics textbook; published concept assessments; and open-source, peer-reviewed curriculum materials. Our findings show that current genetics assessment questions overwhelmingly emphasize the impact of genes on phenotypes and that the effect of the environment is rarely addressed. These results indicate a need for the inclusion of more multifactorial genetics concepts, and we suggest ways to introduce them into undergraduate courses.
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Team-Based Learning (TBL) is a pedagogical tool that has great potential to develop student engagement, accountability, and equity in the online classroom. TBL is rooted in evidence-based educational theories and practices that underlie many active learning approaches such as self-testing, team discussion, and application of knowledge. The use of these approaches is associated with better student performance, retention, and sense of belonging in the classroom, aspects that are often reported to be especially lacking in online courses. Here, we describe how we implemented TBL in a face-to-face and an online introductory level evolution and biodiversity course. We implemented TBL in the face-to-face course (~200 students) starting in 2018 and in the online course (~30 students) starting in the summer of 2019. We used several online applications to facilitate the transition to an online platform such as Simbio, Slack, VoiceThread, Articulate 360, and Teammates. Our experiences using TBL approaches in the online course have been rewarding, and students are engaged and accountable for their learning and performed well in the course. Our goal is to provide an example of how we designed a life science course using TBL approaches and transitioned the course to an online environment. With the current switch to remote instruction and online learning, we recommend the use of TBL as a course design approach that can improve the students' online learning experience.
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BACKGROUND: The first day of class helps students learn about what to expect from their instructors and courses. Messaging used by instructors, which varies in content and approach on the first day, shapes classroom social dynamics and can affect subsequent learning in a course. Prior work established the non-content Instructor Talk Framework to describe the language that instructors use to create learning environments, but little is known about the extent to which students detect those messages. In this study, we paired first day classroom observation data with results from student surveys to measure how readily students in introductory STEM courses detect non-content Instructor Talk. RESULTS: To learn more about the instructor and student first day experiences, we studied 11 introductory STEM courses at two different institutions. The classroom observation data were used to characterize course structure and use of non-content Instructor Talk. The data revealed that all instructors spent time discussing their instructional practices, building instructor/student relationships, and sharing strategies for success with their students. After class, we surveyed students about the messages their instructors shared during the first day of class and determined that the majority of students from within each course detected messaging that occurred at a higher frequency. For lower frequency messaging, we identified nuances in what students detected that may help instructors as they plan their first day of class. CONCLUSIONS: For instructors who dedicate the first day of class to establishing positive learning environments, these findings provide support that students are detecting the messages. Additionally, this study highlights the importance of instructors prioritizing the messages they deem most important and giving them adequate attention to more effectively reach students. Setting a positive classroom environment on the first day may lead to long-term impacts on student motivation and course retention. These outcomes are relevant for all students, but in particular for students in introductory STEM courses which are often critical prerequisites for being in a major. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40594-021-00306-y.
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Student impressions formed during the first day of class can impact course satisfaction and performance. Despite its potential importance, little is known about how instructors format the first day of class. Here, we report on observations of the first day of class in 23 introductory science, technology, engineering, and math (STEM) courses. We first described how introductory STEM instructors structure their class time by characterizing topics covered on the first day through inductive coding of class videos. We found that all instructors discussed policies and basic information. However, a cluster analysis revealed two groups of instructors who differed primarily in their level of STEM content coverage. We then coded the videos with the noncontent Instructor Talk framework, which organizes the statements instructors make unrelated to disciplinary content into several categories and subcategories. Instructors generally focused on building the instructor-student relationship and establishing classroom culture. Qualitative analysis indicated that instructors varied in the specificity of their noncontent statements and may have sent mixed messages by making negatively phrased statements with seemingly positive intentions. These results uncovered variation in instructor actions on the first day of class and can help instructors more effectively plan this day by providing messages that set students up for success.
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Ingeniería , Estudiantes , Humanos , Matemática , TecnologíaRESUMEN
Active learning is frequently used to describe teaching practices, but the term is not well-defined in the context of undergraduate biology education. To clarify this term, we explored how active learning is defined in the biology education literature (n = 148 articles) and community by surveying a national sample of biology education researchers and instructors (n = 105 individuals). Our objectives were to increase transparency and reproducibility of teaching practices and research findings in biology education. Findings showed the majority of the literature concerning active learning never defined the term, but the authors often provided examples of specific active-learning strategies. We categorized the available active-learning definitions and strategies obtained from the articles and survey responses to highlight central themes. Based on data from the BER literature and community, we provide a working definition of active learning and an Active-Learning Strategy Guide that defines 300+ active-learning strategies. These tools can help the community define, elaborate, and provide specificity when using the term active learning to characterize teaching practices.
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Biología , Aprendizaje Basado en Problemas , Biología/educación , Humanos , Reproducibilidad de los Resultados , Investigadores , EnseñanzaRESUMEN
The Vision and Change report called for the biology community to mobilize around teaching the core concepts of biology. This essay describes a collection of resources developed by several different groups that can be used to respond to the report's call to transform undergraduate education at both the individual course and departmental levels. First, we present two frameworks that help articulate the Vision and Change core concepts, the BioCore Guide and the Conceptual Elements (CE) Framework, which can be used in mapping the core concepts onto existing curricula and designing new curricula that teach the biology core concepts. Second, we describe how the BioCore Guide and the CE Framework can be used alongside the Partnership for Undergraduate Life Sciences Education curricular rubric as a way for departments to self-assess their teaching of the core concepts. Finally, we highlight three sets of instruments that can be used to directly assess student learning of the core concepts: the Biology Card Sorting Task, the Biology Core Concept Instruments, and the Biology-Measuring Achievement and Progression in Science instruments. Approaches to using these resources independently and synergistically are discussed.
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Curriculum , Biología/educación , Humanos , Estudiantes , EnseñanzaRESUMEN
Assessing learning across a biology major can help departments monitor achievement of broader program-level goals and identify opportunities for curricular improvement. However, biology departments have lacked suitable tools to measure learning at the program scale. To address this need, we developed four freely available assessments-called Biology-Measuring Achievement and Progression in Science or Bio-MAPS-for general biology, molecular biology, ecology/evolution, and physiology programs. When administered at multiple time points in a curriculum, these instruments can provide departments with information on how student conceptual understanding changes across a major and help guide curricular modifications to enhance learning.
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The Vision and Change report provides a nationally agreed upon framework of core concepts that undergraduate biology students should master by graduation. While identifying these concepts was an important first step, departments also need ways to measure the extent to which students understand these concepts. Here, we present the General Biology-Measuring Achievement and Progression in Science (GenBio-MAPS) assessment as a tool to measure student understanding of the core concepts at key time points in a biology degree program. Data from more than 5000 students at 20 institutions reveal that this instrument distinguishes students at different stages of the curriculum, with an upward trend of increased performance at later time points. Despite this trend, we identify several concepts that advanced students find challenging. Linear mixed-effects models reveal that gender, race/ethnicity, English-language status, and first-generation status predict overall performance and that different institutions show distinct performance profiles across time points. GenBio-MAPS represents the first programmatic assessment for general biology programs that spans the breadth of biology and aligns with the Vision and Change core concepts. This instrument provides a needed tool to help departments monitor student learning and guide curricular transformation centered on the teaching of core concepts.
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Biología/educación , Comprensión , Evaluación Educacional , Estudiantes , Curriculum , Demografía , Femenino , Humanos , Modelos Lineales , MasculinoRESUMEN
College science instructors need continuous professional development (PD) to meet the call to evidence-based practice. New PD efforts need to focus on the nuanced blend of factors that influence instructors' teaching practices. We used persona methodology to describe the diversity among instructors who were participating in a long-term PD initiative. Persona methodology originates from ethnography. It takes data from product users and compiles those data in the form of fictional characters. Personas facilitate user-centered design. We identified four personas among our participants: Emma the Expert views herself as the subject-matter expert in the classroom and values her hard-earned excellence in lecturing. Ray the Relater relates to students and focuses on their points of view about innovative pedagogies. Carmen the Coach coaches her students by setting goals for them and helping them develop skill in scientific practices. Beth the Burdened owns the responsibility for her students' learning and feels overwhelmed that students still struggle despite her use of evidence-based practice. Each persona needs unique PD. We suggest ways that PD facilitators can use our personas as a reflection tool to determine how to approach the learners in their PD. We also suggest further avenues of research on learner-centered PD.
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Educación Profesional , Docentes , Aprendizaje , Femenino , Humanos , Masculino , Estudiantes , EnseñanzaRESUMEN
The instructional practices used in introductory college courses often differ dramatically from those used in high school courses, and dissatisfaction with these practices is cited by students as a prominent reason for leaving science, technology, engineering, and mathematics (STEM) majors. To better characterize the transition to college course work, we investigated the extent to which incoming expectations of course activities differ based on student demographic characteristics, as well as how these expectations align with what students will experience. We surveyed more than 1500 undergraduate students in large introductory STEM courses at three research-intensive institutions during the first week of classes about their expectations regarding how class time would be spent in their courses. We found that first-generation and first-semester students predict less lecture than their peers and that class size had the largest effect on student predictions. We also collected classroom observation data from the courses and found that students generally underpredicted the amount of lecture observed in class. This misalignment between student predictions and experiences, especially for first-generation and first-semester college students and students enrolled in large- and medium-size classes, has implications for instructors and universities as they design curricula for introductory STEM courses with explicit retention goals.