If you are learner-centered and you know it, raise your hand: Perspectives on and implementation of pedagogical changes by science instructors during the COVID-19 pandemic.

Students at Minority-Serving Institutions (MSIs) faced significant hardships while trying to learn through emergency remote teaching (ERT) during the COVID-19 pandemic. Our research aims to investigate if science, technology, engineering, and mathematics (STEM) instructors thought about and enacted more learner-centered teaching practices to alleviate some of this stress encountered by their students. Using semi-structured interviews and classroom observations, we utilized inductive and deductive qualitative research methods to examine two questions: (1) To what extent were STEM instructor's perceived pedagogical changes learner-centered during ERT?; and (2) To what extent were STEM instructor's teaching behaviors and discourse practices learner-centered during ERT? Our findings revealed that during ERT, STEM instructors described using a variety of pedagogical changes that we identified as learner-centered under the Weimer framework, including ideas such as enacting flexible late policies and increased usage of formative assessment. Interestingly, we found that many of these learned-centered changes were happening outside of the classroom. Classroom observations assessing instructor behaviors and discourse demonstrated that STEM instructors enacted practices that aligned with Weimer's five constructs of learner-centered teaching. Our research highlights implications of learner-centered teaching practices for STEM instructors as well as researchers.

Collaborative Teaching plus (CT+): A Timely, Flexible, and Dynamic Course Design Implemented during Emergency Remote Teaching in an Introductory Biology Course.

Student-centered pedagogies promote student learning in college science, technology, engineering, and mathematics (STEM) classrooms. However, transitioning to active learning from traditional lecturing may be challenging for both students and instructors. This case study presents the development, implementation, and assessment of a modified collaborative teaching (CT) and team-based learning (TBL) approach (CT plus TBL, or CT+) in an introductory biology course at a Minority-Serving Institution. A logic model was formulated depicting the various assessment practices with the culminating goal of improving the student learning experience. We analyzed qualitative and quantitative data based on students and instructors' behaviors and discourse, and student midsemester and end-of-semester surveys. Our findings revealed that the integration of multiple instructors allowed for knowledge exchange in blending complementary behaviors and discourse practices during class sessions. In addition, the frequent ongoing assessments and incorporation of student feedback informed the CT+ design during both in-person and emergency remote teaching. Furthermore, this course design could be easily adapted to a variety of STEM courses in higher education, including remote instruction.

Predicting implementation of active learning by tenure-track teaching faculty using robust cluster analysis.

Background: The University of California system has a novel tenure-track education-focused faculty position called Lecturer with Security of Employment (working titles: Teaching Professor or Professor of Teaching). We focus on the potential difference in implementation of active-learning strategies by faculty type, including tenure-track education-focused faculty, tenure-track research-focused faculty, and non-tenure-track lecturers. In addition, we consider other instructor characteristics (faculty rank, years of teaching, and gender) and classroom characteristics (campus, discipline, and class size). We use a robust clustering algorithm to determine the number of clusters, identify instructors using active learning, and to understand the instructor and classroom characteristics in relation to the adoption of active-learning strategies. Results: We observed 125 science, technology, engineering, and mathematics (STEM) undergraduate courses at three University of California campuses using the Classroom Observation Protocol for Undergraduate STEM to examine active-learning strategies implemented in the classroom. Tenure-track education-focused faculty are more likely to teach with active-learning strategies compared to tenure-track research-focused faculty. Instructor and classroom characteristics that are also related to active learning include campus, discipline, and class size. The campus with initiatives and programs to support undergraduate STEM education is more likely to have instructors who adopt active-learning strategies. There is no difference in instructors in the Biological Sciences, Engineering, or Information and Computer Sciences disciplines who teach actively. However, instructors in the Physical Sciences are less likely to teach actively. Smaller class sizes also tend to have instructors who teach more actively. Conclusions: The novel tenure-track education-focused faculty position within the University of California system represents a formal structure that results in higher adoption of active-learning strategies in undergraduate STEM education. Campus context and evolving expectations of the position (faculty rank) contribute to the symbols related to learning and teaching that correlate with differential implementation of active learning. Supplementary Information: The online version contains supplementary material available at 10.1186/s40594-022-00365-9.

Increasing Student Engagement through Course Attributes, Community, and Classroom Technology: Lessons from the Pandemic.

While many STEM (science, technology, engineering, and mathematics) instructors returned to in-person instruction in fall 2021, others found themselves continuing to teach via online, hybrid, or hybrid flexible (i.e., hyflex) formats. Regardless of one's instructional modality, the findings from our own and other studies provided insight into effective strategies for increasing student engagement and decreasing cognitive overload. As part of this perspective, we included data from undergraduate students, many of whom are first generation and low income and from marginalized backgrounds, to identify instructional practices that helped them thrive and succeed during the recent COVID-19 pandemic. More specifically, we explored the various pedagogies and technologies utilized during emergency remote teaching to identify best practices as we considered the future of teaching. In sharing best practices at our institution, we aimed to provide a framework for deep reflection among the readers and the identification of practices to start, stop, and/or continue at their own institutions.

Correction to: I will teach you here or there, I will try to teach you anywhere: perceived supports and barriers for emergency remote teaching during the COVID-19 pandemic.

[This corrects the article DOI: 10.1186/s40594-022-00335-1.].

I will teach you here or there, I will try to teach you anywhere: perceived supports and barriers for emergency remote teaching during the COVID-19 pandemic.

BACKGROUND: Due to the COVID-19 pandemic, many universities moved to emergency remote teaching (ERT). This allowed institutions to continue their instruction despite not being in person. However, ERT is not without consequences. For example, students may have inadequate technological supports, such as reliable internet and computers. Students may also have poor learning environments at home and may need to find added employment to support their families. In addition, there are consequences to faculty. It has been shown that female instructors are more disproportionately impacted in terms of mental health issues and increased domestic labor. This research aims to investigate instructors' and students' perceptions of their transition to ERT. Specifically, during the transition to ERT at a research-intensive, Minority-Serving Institution (MSI), we wanted to: (1) Identify supports and barriers experienced by instructors and students. (2) Compare instructors' experiences with the students' experiences. (3) Explore these supports and barriers within the context of social presence, teaching presence, and/or cognitive presence as well as how these supports and barriers relate to scaffolding in STEM courses. RESULTS: Instructors identified twice as many barriers as supports in their teaching during the transition to ERT and identified casual and formal conversations with colleagues as valuable supports. Emerging categories for barriers consisted of academic integrity concerns as well as technological difficulties. Similarly, students identified more barriers than supports in their learning during the transition to ERT. More specifically, students described pre-existing course structure, classroom technology, and community as best supporting their learning. Barriers that challenged student learning included classroom environment, student availability, and student emotion and comfort. CONCLUSIONS: Together, this research will help us understand supports and barriers to teaching and learning during the transition to ERT. This understanding can help us better plan and prepare for future emergencies, particularly at MSIs, where improved communication and increased access to resources for both students and instructors are key. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40594-022-00335-1.

Look Who's Talking: Teaching and Discourse Practices across Discipline, Position, Experience, and Class Size in STEM College Classrooms.

Students are more likely to learn in college science, technology, engineering, and math (STEM) classrooms when instructors use teacher discourse moves (TDMs) that encourage student engagement and learning. However, although teaching practices are well studied, TDMs are not well understood in college STEM classrooms. In STEM courses at a minority-serving institution (MSI; n = 74), we used two classroom observation protocols to investigate teaching practices and TDMs across disciplines, instructor types, years of teaching experience, and class size. We found that instructors guide students in active learning activities, but they use authoritative discourse approaches. In addition, chemistry instructors presented more than biology instructors. Also, teaching faculty had relatively high dialogic, interactive discourse, and neither years of faculty teaching experience nor class size had an impact on teaching practices or TDMs. Our results have implications for targeted teaching professional development efforts across instructor and course characteristics to improve STEM education at MSIs.

The Classroom Discourse Observation Protocol (CDOP): A quantitative method for characterizing teacher discourse moves in undergraduate STEM learning environments.

We describe the development and validation of a new instrument, the Classroom Discourse Observation Protocol (CDOP), which quantifies teacher discourse moves (TDMs) from observational data in undergraduate STEM classrooms. TDMs can be conceptualized as epistemic tools that can mediate classroom discussions. Through an inductive-deductive coding process, we identified commonly occurring TDMs among a group of biology instructors (n = 13, 37 class session) teaching in Active Learning Environments. We describe the CDOP coding scheme and its associated matrix that allows observers to reliably characterize TDMs in 2-min time intervals over the course of a class period. We present the protocol, discuss how it differs from existing classroom observation protocols, and describe the process by which it was developed and validated. Also, we show how this protocol is able to discriminate the discursive practices of instructors teaching in undergraduate STEM learning environments with sample qualitative and quantitative results that illustrate its utility for assessing and improving STEM instructional practices.

Chironomidae (Diptera) species diversity of estuaries across a land use gradient on the Caribbean coast of Costa Rica / Diversidad de especies de Chironomidae (Diptera) de estuarios en un gradiente de uso de suelo en la costa Caribe de Costa Rica

Abstract The family Chironomidae (Diptera) is the most widely distributed, most diverse, and often the most abundant of all families of benthic macroinvertebrates in aquatic ecosystems, including estuaries and other coastal marine ecosystems. Chironomid assemblages are likely to provide a useful measure of biotic integrity in estuaries of Costa Rica, which lack an intensive estuarine bioassessment tool to support environmental monitoring and regulatory programs. We characterized the taxonomic composition of Chironomidae, tested a Chironomidae Index of Biotic Integrity (CIBI) developed from extrinsic pollution tolerance values for its efficacy in evaluating the surface water quality and physical habitat, and made recommendations for increasing the sensitivity of the CIBI to detect differing degrees of stress across a range of estuaries in Costa Rica. Specifically, we selected nine estuaries within six different watersheds across a land use gradient located on the Caribbean coast of Costa Rica and collected Chironomidae surface-floating pupal exuviae (SFPE) samples biannually for two consecutive years (July 2012, Jan. 2013, July 2013, Jan. 2014). We identified 228 morphospecies and 70 genera from 17 071 Chironomidae pupal exuviae collected from nine estuaries, which ranked in the following order from lowest to highest biotic integrity based on CIBI scores: Estero Negro, Laguna Cuatro, Laguna Jalova, Laguna del Tortuguero, Río Parismina, Laguna Barra del Colorado, Río Pacuare, Río Bananito, and Río Estrella. The CIBI successfully differentiated between estuaries with poor versus good biotic integrity, indicating that CIBI could be used to evaluate the surface water quality and physical habitat of Costa Rican estuaries. We recommend that future studies refine our approach by developing regionally accurate genus and corresponding species-level tolerance values to improve the sensitivity of the CIBI for biological monitoring of Costa Rican estuaries. Rev. Biol. Trop. 66(3): 1118-1134. Epub 2018 September 01.

Resumen La familia Chironomidae (Diptera) es la más ampliamente distribuida, más diversa y a menudo, la más abundante de todas las familias de macroinvertebrados bentónicos en ecosistemas acuáticos, incluyendo estuarios y otros ecosistemas marinos. Probablemente, los ensambles de quironómidos proporcionen una medida útil de integridad biótica en estuarios de Costa Rica, los cuales carecen de una herramienta de evaluación biológica que respalde programas de monitoreo ambiental y programas regulatorios. Caracterizamos la composición taxonómica de Chironomidae, probamos un Índice de Integridad Biótica de Chironomidae (CIBI) desarrollado a partir de valores de tolerancia de contaminación extrínseca, por su eficacia en evaluar la calidad de la superficie del agua y el hábitat físico. Además, realizamos recomendaciones para incrementar la sensibilidad del CIBI para detectar diferentes grados de estrés en un rango de estuarios en Costa Rica. Específicamente, seleccionamos nueve estuarios dentro de seis cuencas diferentes a lo largo de un gradiente de uso de suelo en la costa Caribe de Costa Rica y recolectamos muestras de las exuvias pupales que flotan en la superficie (SFPE) por dos años consecutivos (Julio 2012, Enero 2013, Julio 2013, Enero 2014). Identificamos 228 morfoespecies y 70 géneros de 17 071 exuvias de pupas de Chironomidae recolectadas en nueve estuarios, los cuales se clasificaron en el siguiente orden de menor a mayor integridad biótica basado en los valores del CIBI: Estero Negro, Laguna Cuatro, Laguna Jalova, Laguna del Tortuguero, Río Parismina, Laguna Barra del Colorado, Río Pacuare, Río Bananito, y Río Estrella. El CIBI diferenció eficazmente entre estuarios con integridad biótica pobre versus buena, indicando que el CIBI puede ser usado para evaluar la calidad de la superficie del agua y el hábitat físico de estuarios de Costa Rica. Recomendamos que estudios futuros refinen nuestro planteamiento desarrollando valores de tolerancia de géneros precisos regionalmente y niveles correspondientes de especies para mejorar la sensibilidad del CIBI para el monitoreo de estuarios de Costa Rica.

Trace DNA from insect skins: a comparison of five extraction protocols and direct PCR on chironomid pupal exuviae.

Insect skins (exuviae) are of extracellular origin and shed during moulting. The skins do not contain cells or DNA themselves, but epithelial cells and other cell-based structures might accidentally attach as they are shed. This source of trace DNA can be sufficient for PCR amplification and sequencing of target genes and aid in species identification through DNA barcoding or association of unknown life stages. Species identification is essential for biomonitoring programs, as species vary in sensitivities to environmental factors. However, it requires a DNA isolation protocol that optimizes the output of target DNA. Here, we compare the relative effectiveness of five different DNA extraction protocols and direct PCR in isolation of DNA from chironomid pupal exuviae. Chironomidae (Diptera) is a species-rich group of aquatic macroinvertebrates widely distributed in freshwater environments and considered a valuable bioindicator of water quality. Genomic DNA was extracted from 61.2% of 570 sampled pupal exuviae. There were significant differences in the methods with regard to cost, handling time, DNA quantity, PCR success, sequence success and the ability to sequence target taxa. The NucleoSpin(®) Tissue XS Kit, DNeasy(®) Blood and Tissue kit, and QuickExtract(™) DNA Extraction Solution provided the best results in isolating DNA from single pupal exuviae. Direct PCR and DTAB/CTAB methods gave poor results. While the observed differences in DNA isolation methods on trace DNA will be relevant to research that focuses on aquatic macroinvertebrate ecology, taxonomy and systematics, they should also be of interest for studies using environmental barcoding and metabarcoding of aquatic environments.

Use of Chironomidae (Diptera) Surface-Floating Pupal Exuviae as a Rapid Bioassessment Protocol for Water Bodies.

Rapid bioassessment protocols using benthic macroinvertebrate assemblages have been successfully used to assess human impacts on water quality. Unfortunately, traditional benthic larval sampling methods, such as the dip-net, can be time-consuming and expensive. An alternative protocol involves collection of Chironomidae surface-floating pupal exuviae (SFPE). Chironomidae is a species-rich family of flies (Diptera) whose immature stages typically occur in aquatic habitats. Adult chironomids emerge from the water, leaving their pupal skins, or exuviae, floating on the water's surface. Exuviae often accumulate along banks or behind obstructions by action of the wind or water current, where they can be collected to assess chironomid diversity and richness. Chironomids can be used as important biological indicators, since some species are more tolerant to pollution than others. Therefore, the relative abundance and species composition of collected SFPE reflect changes in water quality. Here, methods associated with field collection, laboratory processing, slide mounting, and identification of chironomid SFPE are described in detail. Advantages of the SFPE method include minimal disturbance at a sampling area, efficient and economical sample collection and laboratory processing, ease of identification, applicability in nearly all aquatic environments, and a potentially more sensitive measure of ecosystem stress. Limitations include the inability to determine larval microhabitat use and inability to identify pupal exuviae to species if they have not been associated with adult males.

Characterization of Chironomidae (Diptera) surface-floating pupal exuviae sample sort time from coastal tropical aquatic systems.

Many studies either ignore chironomids or only identify specimens to subfamily or tribe due to the associated difficulty and high cost with processing and identifying larvae. An efficient form of sampling chironomids involves collections of surface-floating pupal exuviae (SFPE). SFPE sample sorting has been shown to be more time efficient than traditional dip-net methods in temperate urban and peri-urban streams. However, no published studies have tested the time efficiency of SFPE sample sorting from coastal tropical aquatic systems. We calculated sort times for SFPE samples collected from a coastal tropical stream and an estuary and used multiple linear regression analysis to quantify the relationship between sample sort time and number of specimens, average body length of specimens, and dry weight of sample residue. The average amount of time required to sort very small samples was 69.3 min, while moderate samples averaged 85.6 min and large samples averaged 153.5 min. However, on average, small samples were nine times more time consuming per specimen than large samples. Additionally, dry weight of small-sized residue and the number of specimens contributed significantly to sort time. Therefore, we recommend collecting larger samples, which can be achieved by sampling for 20 min over 200-m reaches for stream sites and 500- to 1,000-m reaches for riverine and estuarine sites. Also, we suggest collecting during periods of low wave action and disturbance by boat wake to reduce the amount of sample residue. This research will enhance project planning and budgeting of future studies using the SFPE method to monitor coastal tropical aquatic systems.