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Even highly motivated undergraduates drift off their STEM career pathways. In large introductory STEM classes, instructors struggle to identify and support these students. To address these issues, we developed co‐redesign methods in partnership with disciplinary experts to create high‐structure STEM courses that better support students and produce informative digital event data. To those data, we applied theory‐ and context‐relevant labels to reflect active and self‐regulated learning processes involving LMS‐hosted course materials, formative assessments, and help‐seeking tools. We illustrate the predictive benefits of this process across two cycles of model creation and reapplication. In cycle 1, we used theory‐relevant features from 3 weeks of data to inform a prediction model that accurately identified struggling students and sustained its accuracy when reapplied in future semesters. In cycle 2, we refit a model with temporally contextualized features that achieved superior accuracy using data from just two class meetings. This modelling approach can produce durable learning analytics solutions that afford scaled and sustained prediction and intervention opportunities that involve explainable artificial intelligence products. Those same products that inform prediction can also guide intervention approaches and inform future instructional design and delivery.Practitioner notesWhat is already known about this topicLearning analytics includes an evolving collection of methods for tracing and understanding student learning through their engagements with learning technologies.Prediction models based on demographic data can perpetuate systemic biases.Prediction models based on behavioural event data can produce accurate predictions of academic success, and validation efforts can enrich those data to reflect students' self‐regulated learning processes within learning tasks.What this paper addsLearning analytics can be successfully applied to predict performance in an authentic postsecondary STEM context, and the use of context and theory as guides for feature engineering can ensure sustained predictive accuracy upon reapplication.The consistent types of learning resources and cyclical nature of their provisioning from lesson to lesson are hallmarks of high‐structure active learning designs that are known to benefit learners. These designs also provide opportunities for observing and modelling contextually grounded, theory‐aligned and temporally positioned learning events that informed prediction models that accurately classified students upon initial and later reapplications in subsequent semesters.Co‐design relationships where researchers and instructors work together toward pedagogical implementation and course instrumentation are essential to developing unique insights for feature engineering and producing explainable artificial intelligence approaches to predictive modelling.Implications for practice and/or policyHigh‐structure course designs can scaffold student engagement with course materials to make learning more effective and products of feature engineering more explainable.Learning analytics initiatives can avoid perpetuation of systemic biases when methods prioritize theory‐informed behavioural data that reflect learning processes, sensitivity to instructional context and development of explainable predictors of success rather than relying on students' demographic characteristics as predictors.Prioritizing behaviours as predictors improves explainability in ways that can inform the redesign of courses and design of learning supports, which further informs the refinement of learning theories and their applications. [ABSTRACT FROM AUTHOR]

The Cenozoic development of the Scotia Sea and opening of Drake Passage evolved in a complex tectonic setting with sea‐floor spreading accompanied by the dispersal of continental fragments and the creation of rifted oceanic basins. The post‐Eocene tectonic setting of the Scotia Sea is relatively well established, but Late Mesozoic palaeo‐locations of many continental fragments prior to dispersal are largely unknown, with almost no geological control on the submerged banks. Detrital zircon analysis of dredged metasedimentary rocks of Bruce Bank from the South Scotia Ridge demonstrates a geological continuity with the South Orkney microcontinent (SOM) and also a clear geological affinity with the Trinity Peninsula Group metasedimentary rocks of the Antarctic Peninsula and components of the Cordillera Darwin Metamorphic Complex of Tierra del Fuego. Kinematic modelling indicates an Antarctic Plate origin for Bruce Bank and the SOM is the most plausible setting, prior to translation to the Scotia Plate during Scotia Sea opening. [ABSTRACT FROM AUTHOR]

Pregnant women are uniquely susceptible to adverse effects of air pollution exposure due to vulnerabilities and health consequences during pregnancy (e.g., hypertensive disorders of pregnancy [HDP]) compared to the general population. Because the Clean Air Act (CAA) creates a duty to protect at‐risk groups, the regulatory assessment of at‐risk populations has both policy and scientific foundations. Previously, pregnant women have not been specially protected in establishing the margin of safety for the ozone and particulate matter (PM) standards. Due to physiological changes, pregnant women can be at greater risk of adverse effects of air pollution and should be considered an at‐risk population. Women with preexisting conditions, women experiencing poverty, and groups that suffer systematic discrimination may be particularly susceptible to cardiac effects of air pollutants during pregnancy. We rigorously reviewed 11 studies of over 1.3 million pregnant women in the United States to characterize the relationship between ozone or PM exposure and HDP. Findings were generally mixed, with a few studies reporting a joint association between ozone or PM and social determinants or pre‐existing chronic health conditions related to HDP. Adequate evidence associates exposure to PM with an adverse effect of HDP among pregnant women not evident among non‐gravid populations. [ABSTRACT FROM AUTHOR]

New information is presented on the configuration of the northern Barents Sea Ice Sheet ( BSIS) during the last glacial and deglaciation (21-11.5 ka). The glacial dynamics of the BSIS that we discuss are based on clay-mineral compositions of subglacial tills and a distinct kaolinite source in the central Barents Sea where previous workers have placed a large, single ice dome for the last glacial BSIS. Our results, which appear to show that subglacial sediments were sourced locally, suggest that the BSIS consisted at least temporarily of multiple domes and may have been more dynamic than previously thought. New radiocarbon dates are presented along with new ice-extent reconstructions for 16.5-15, 14, 13.5 and 11.5 ka. Our reconstructions add information to previous regional and continental-scale efforts in areas east of Svalbard. Ice retreat in the northern Barents Sea progressed as follows. (i) 19-16.5 ka. Major calving led to dynamic thinning in shelf troughs and was accompanied by significant ice-sheet thinning inland as a result of ice drawdown. (ii) 16.5-15 ka. Rapid ice-margin retreat of between 75-100 km occurred, via lift-off and iceberg calving, in Hinlopen and Kvitøya troughs, as well as major retreat (>300 km) in Franz Victoria Trough ( FVT) further east. (iii) 15-13.5 ka. Retreat progressed westwards from the FVT towards Svalbard with troughs east of Svalbard (Kvitøya, Olga, and Erik Eriksen) mostly ice-free by 13.5 ka. (iv) 13.5-11.5 ka. Ice retreated gradually towards residual ice masses on Svalbard, Kong Karls Land and possibly Storbanken. Our data require a modification of earlier views of the BSIS because they point toward a more dynamic ice sheet and decay that, once initiated at the shelf break, was dominated by the withdrawal of ice from the FVT that progressed westwards towards the Svalbard archipelago. [ABSTRACT FROM AUTHOR]

Ice stream bed topography contains key evidence for the ways ice streams interact with, and are potentially controlled by, their beds. Here we present the first application of two-dimensional Fourier analysis to 22 marine and terrestrial topographies from 5 regions in Antarctica and Canada, with and without mega-scale glacial lineations (MSGLs). We find that the topography of MSGL-rich ice stream sedimentary beds is characterized by multiple, periodic wavelengths between 300 and 1200 m and amplitudes from decimeters to a few meters. This periodic topography is consistent with the idea that instability is a key element to the formation of MSGL bedforms. Dominant wavelengths vary among locations and, on one paleo ice stream bed, increase along the direction of ice flow by 1.7 ± 0.52% km−1. We suggest that these changes are likely to reflect pattern evolution via downstream wavelength coarsening, even under potentially steady ice stream geometry and flow conditions. The amplitude of MSGLs is smaller than that of other fluvial and glacial topographies but within the same order of magnitude. However, MSGLs are a striking component of ice stream beds because the topographic amplitude of features not aligned with ice flow is reduced by an order of magnitude relative to those oriented with the flow direction. This study represents the first attempt to automatically derive the spectral signatures of MSGLs. It highlights the plausibility of identifying these landform assemblages using automated techniques and provides a benchmark for numerical models of ice stream flow and subglacial landscape evolution. [ABSTRACT FROM AUTHOR]

Turbid meltwater plumes and ice-proximal fans occur where subglacial streams reach the grounded marine margins of modern and ancient tidewater glaciers. However, the spacing and temporal stability of these subglacial channels is poorly understood. This has significant implications for understanding the geometry and distribution of Quaternary and ancient ice-proximal fans that can form important aquifers and hydrocarbon reservoirs. Remote-sensing and numerical-modelling techniques are applied to the 200 km long marine margin of a Svalbard ice cap, Austfonna, to quantify turbid meltwater-plume distribution and predict its temporal stability. Results are combined with observations from geophysical data close to the modern ice front to refine existing depositional models for ice-proximal fans. Plumes are spaced ca 3 km apart and their distribution along the ice front is stable over decades. Numerical modelling also predicts the drainage pattern and meltwater discharge beneath the ice cap; modelled water-routing patterns are in reasonable agreement with satellite-mapped plume locations. However, glacial retreat of several kilometres over the past 40 years has limited build-up of significant ice-proximal fans. A single fan and moraine ridge is noted from marine-geophysical surveys. Closer to the ice front there are smaller recessional moraines and polygonal sediment lobes but no identifiable fans. Schematic models of ice-proximal deposits represent varying glacier-terminus stability: (i) stable terminus where meltwater sedimentation produces an ice-proximal fan; (ii) quasi-stable terminus, where glacier readvance pushes or thrusts up ice-proximal deposits into a morainal bank; and (iii) retreating terminus, with short still-stands, allowing only small sediment lobes to build up at melt-stream portals. These modern investigations are complemented with outcrop and subsurface observations and numerical modelling of an ancient, Ordovician glacial system. Thick turbidite successions and large fans in the Late Ordovician suggest either high-magnitude events or sustained high discharge, consistent with a relatively mild palaeo-glacial setting for the former North African ice sheet. [ABSTRACT FROM AUTHOR]

Problem Group B Streptococcus ( GBS) is a leading cause of neonatal morbidity and mortality. We tested the hypothesis that the choriodecidua plays a role in GBS-stimulated human beta defensin( HBD)-2 increases in amnion cells through a secreted factor of choriodecidual origin. Method of study Human amnion epithelial cells were treated with choriodecidual GBS-conditioned medium, live GBS, lipoteichoic acid ( LTA), or lipopolysaccharide ( LPS), with and without IL-1 inhibitors. Results Choriodecidual tissue punches released IL-1α and IL-1β in response to GBS and this medium significantly stimulated release of HBD-2 by amnion cell cultures. Inhibitors of IL-1 significantly impaired the release of HBD-2 from amnion cells treated with GBS choriodecidual conditioned medium. Direct stimulation of amnion cells with GBS, LTA, or LPS did not increase HBD-2 release. Conclusion Paracrine signaling involving IL-1 of choriodecidual origin is likely a critical driver for amnion HBD-2 increases in response to GBS infection of extraplacental membranes. [ABSTRACT FROM AUTHOR]

Animals can attempt to reduce uncertainty about their environment by gathering information personally or by observing others' interactions with the environment. There are several sensory modalities that can be used to transmit social information from chemical to visual to audible cues. When predation risk is variable, visual cues of conspecific behavior might be especially telling about the presence of a potential threat; however, most studies couple visual and chemical cues together. Here, we tested whether visual behavioral cues from frightened conspecifics were sufficient to indirectly transfer information about the presence of an unseen predator in three-spined sticklebacks. Our results demonstrate that visual behavioral cues from conspecifics about the presence of a predator are sufficient to induce an antipredator response. This suggests that information transfer can occur rapidly in the absence of chemical cues and that some individuals weigh social information more heavily than others. [ABSTRACT FROM AUTHOR]

Summary. The interaction of platelets with fibrinogen is a key event in the maintenance of a haemostatic response. It has been shown that the 12-carboxy-terminal residues of the γ-chain of fibrinogen mediate platelet adhesion to immobilized fibrinogen. These studies, however, did not exclude the possibility that other domains of fibrinogen are involved in interactions with platelets. To obtain more insight into the involvement of other domains of fibrinogen in platelet adhesion, we studied platelet adhesion in flowing blood to patient dysfibrinogen Vlissingen/Frankfurt IV (V/FIV), to several variant recombinant fibrinogens with abnormalities in the γ-chain segments γ318–320 and γ408–411. Perfusion studies at physiological shear rates showed that platelet adhesion was absent to γΔ408-411, slightly reduced to the heterozygous patient dysfibrinogen V/FIV and strongly reduced to the homozygous recombinant fibrinogens: γΔ319-320, γ318Asp→Ala and γ320Asp→Ala. Furthermore, antibodies raised against the sequences γ308–322 and γ316–333 inhibited platelet adhesion under shear conditions. These experiments indicated that the overlapping segment γ316–322 contains amino acids that could be involved in platelet adhesion to immobilized fibrinogen under flow conditions. In soluble fibrinogen, this sequence is buried inside the fibrinogen molecule and becomes exposed after polymerization. In addition, we have shown that this fibrin-specific sequence also becomes exposed when fibrinogen is immobilized on a surface. [ABSTRACT FROM AUTHOR]

The interaction of platelets with fibrinogen is a key event in the maintenance of a haemostatic response. It has been shown that the 12-carboxy-terminal residues of the gamma-chain of fibrinogen mediate platelet adhesion to immobilized fibrinogen. These studies, however, did not exclude the possibility that other domains of fibrinogen are involved in interactions with platelets. To obtain more insight into the involvement of other domains of fibrinogen in platelet adhesion, we studied platelet adhesion in flowing blood to patient dysfibrinogen Vlissingen/Frankfurt IV (V/FIV), to several variant recombinant fibrinogens with abnormalities in the gamma-chain segments gamma318-320 and gamma408-411. Perfusion studies at physiological shear rates showed that platelet adhesion was absent to gammaDelta408-411, slightly reduced to the heterozygous patient dysfibrinogen V/FIV and strongly reduced to the homozygous recombinant fibrinogens: gammaDelta319-320, gamma318Asp-->Ala and gamma320Asp-->Ala. Furthermore, antibodies raised against the sequences gamma308-322 and gamma316-333 inhibited platelet adhesion under shear conditions. These experiments indicated that the overlapping segment gamma316-322 contains amino acids that could be involved in platelet adhesion to immobilized fibrinogen under flow conditions. In soluble fibrinogen, this sequence is buried inside the fibrinogen molecule and becomes exposed after polymerization. In addition, we have shown that this fibrin-specific sequence also becomes exposed when fibrinogen is immobilized on a surface.