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Teacher reflection is essential for K-12 classrooms, including effective and personalized instruction. Multimodal Learning Analytics (MMLA), integrating data from digital and physical learning environments, could support teacher reflection. Classroom data collected from sensors and TEL environments are needed to produce such analytics. These novel data collection methods pose an open challenge of how MMLA research practices can ensure alignment with teachers’ needs and concerns. This study explores K-12 teachers’ perceptions and preferences regarding MMLA analytics and data sharing. Through a mixed-method survey, we explore teachers’ (N=100) preferences for analytics that help them reflect on their teaching practices, their favored data collection modalities, and data-sharing preferences. Results indicate that teachers were most interested in student learning analytics and their interactions and ways of motivating students. However, they were also significantly less accepting of collecting students’ audio and position data compared to such data about themselves. Finally, teachers were less willing to share data about themselves than their students. Our findings contribute ethical, practical, and pedagogical considerations of MMLA analytics for teacher reflection, informing the research practices and development of MMLA within TEL. 

G protein coupled receptors (GPCRs) exhibit varying degrees of selectivity for different G protein isoforms. Despite the abundant structures of GPCR-G protein complexes, little is known about the mechanism of G protein coupling specificity. The β2-adrenergic receptor is an example of GPCR with high selectivity for Gαs, the stimulatory G protein for adenylyl cyclase, and much weaker for the Gαi family of G proteins inhibiting adenylyl cyclase. By developing a new Gαi-biased agonist (LM189), we provide structural and biophysical evidence supporting that distinct conformations at ICL2 and TM6 are required for coupling of the different G protein subtypes Gαs and Gαi. These results deepen our understanding of G protein specificity and bias and can accelerate the design of ligands that select for preferred signaling pathways. 

G protein-coupled receptors (GPCRs) represent the largest group of membrane receptors for transmembrane signal transduction. Ligand-induced activation of GPCRs triggers G protein activation followed by various signaling cascades. Understanding the structural and energetic determinants of ligand binding to GPCRs and GPCRs to G proteins is crucial to the design of pharmacological treatments targeting specific conformations of these proteins to precisely control their signaling properties. In this study, we focused on interactions of a prototypical GPCR, beta-2 adrenergic receptor (β 2 AR), with its endogenous agonist, norepinephrine (NE), and the stimulatory G protein (G s ). Using molecular dynamics (MD) simulations, we demonstrated the stabilization of cationic NE, NE(+), binding to β 2 AR by G s protein recruitment, in line with experimental observations. We also captured the partial dissociation of the ligand from β 2 AR and the conformational interconversions of G s between closed and open conformations in the NE(+)–β 2 AR–G s ternary complex while it is still bound to the receptor. The variation of NE(+) binding poses was found to alter G s α subunit (G s α) conformational transitions. Our simulations showed that the interdomain movement and the stacking of G s α α1 and α5 helices are significant for increasing the distance between the G s α and β 2 AR, which may indicate a partial dissociation of G s α The distance increase commences when G s α is predominantly in an open state and can be triggered by the intracellular loop 3 (ICL3) of β 2 AR interacting with G s α, causing conformational changes of the α5 helix. Our results help explain molecular mechanisms of ligand and GPCR-mediated modulation of G protein activation. 

Atmospheric CO₂ concentrations have been growing steadily with no sign of moderation. Rubisco is the ubiquitous plant enzyme responsible for carbon fixation in biomass. Expanding luscious forests on Earth would increase CO₂ absorption, but extreme drought, deforestation, desertification, and urbanization encroaching on agricultural land demonstrate the opposite trend. Direct air capture (DAC) from ambient air is the only meaningful way to reduce atmospheric CO₂. We are designing Rubisco-inspired reversible CO₂ DAC systems based on the lysine carbamylation associated with Rubisco activation. Here, we report the results of computational studies of the thermodynamics of CO₂ capture by small alkylamines in aqueous solution to learn about the carbamylation of the amino group in lysine's sidechain. We determined the reaction energies of the carbamylation reactions based on the traditional approach of considering just the most stable structures and based on the ensemble energies computed with the Boltzmann distribution. View the article. 

It might be highly effective if students could transition dynamically between individual and collaborative learning activities, but how could teachers manage such complex classroom scenarios? Although recent work in AIED has focused on teacher tools, little is known about how to orchestrate dynamic transitions between individual and collaborative learning. We created a novel technology ecosystem that supports these dynamic transitions. The ecosystem integrates a novel teacher orchestration tool that provides monitoring support and pairing suggestions with two AI-based tutoring systems that support individual and collaborative learning, respectively. We tested the feasibility of this ecosystem in a classroom study with 5 teachers and 199 students over 22 class sessions. We found that the teachers were able to manage the dynamic transitions and valued them. The study contributes a new technology ecosystem for dynamically transitioning between individual and collaborative learning, plus insight into the orchestration functionality that makes these transitions feasible. 

Site U1561 (30˚43.2902′S, 26˚41.7162′W; proposed Site SATL-55A) is in the central South Atlantic Ocean at a water depth of 4910 meters below sea level (mbsl) ~1250 km west of the Mid-Atlantic Ridge (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024d]) on crust that formed at a slow half spreading rate of ~13.5 mm/y, which is the slowest spreading rate in the study region (Kardell et al., 2019; Christeson et al., 2020; see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024d]). With an estimated age of 61.2 Ma, Site U1561 is the oldest location of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393). Site U1561 sits on a basement ridge and is therefore less heavily sedimented than Sites U1556 and U1557, which are located ~25 km south of Site U1561 on 61.2 and 60.7 Ma ocean crust, respectively. Together, all sites in this region allow for investigation of the effect of sediment thickness on crustal evolution. 

Site U1558 (30°53.7814′S, 24°50.4822′W; proposed Site SATL-43A) is in the central South Atlantic Ocean at a water depth of ~4334 meters below sea level (mbsl) ~1067 km west of the Mid-Atlantic Ridge (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024c]) on crust that formed at a slow half spreading rate of ~19.5 mm/y (Kardell et al., 2019; Christeson et al., 2020) (see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024c]). With an estimated age of 49.2 Ma, Site U1558 is the second oldest location of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393). 

Site U1557 (30°56.4651′S, 26°37.7892′W, proposed Site SATL-56A) is in the central South Atlantic Ocean at a water depth of ~5011 meters below sea level (mbsl) ~1243 km west of the Mid-Atlantic Ridge (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024d]) on crust that formed at a slow half spreading rate of ~13.5 mm/y, which is the slowest spreading rate in the study region (Kardell et al., 2019; Christeson et al., 2020) (see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024d]; Reece et al., 2016; Reece and Estep, 2019). With an estimated age of 60.7 Ma, Site U1557 is just about the oldest location of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393). Site U1557 is more heavily sedimented than Site U1556, which is located 6.5 km west of Site U1557 on 61.2 Ma ocean crust. Together, both sites allow for investigation of the effect of sediment thickness on crustal evolution.