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Abstract. Marine diazotrophs convert dinitrogen (N2) gas intobioavailable nitrogen (N), supporting life in the global ocean. In 2012, thefirst version of the global oceanic diazotroph database (version 1) waspublished. Here, we present an updated version of the database (version 2),significantly increasing the number of in situ diazotrophic measurements from13 565 to 55 286. Data points for N2 fixation rates, diazotrophic cellabundance, and nifH gene copy abundance have increased by 184 %, 86 %, and809 %, respectively. Version 2 includes two new data sheets for the nifH genecopy abundance of non-cyanobacterial diazotrophs and cell-specific N2fixation rates. The measurements of N2 fixation rates approximatelyfollow a log-normal distribution in both version 1 and version 2. However,version 2 considerably extends both the left and right tails of thedistribution. Consequently, when estimating global oceanic N2 fixationrates using the geometric means of different ocean basins, version 1 andversion 2 yield similar rates (43–57 versus 45–63 Tg N yr−1; rangesbased on one geometric standard error). In contrast, when using arithmeticmeans, version 2 suggests a significantly higher rate of 223±30 Tg N yr−1 (mean ± standard error; same hereafter) compared to version 1(74±7 Tg N yr−1). Specifically, substantial rate increases areestimated for the South Pacific Ocean (88±23 versus 20±2 Tg N yr−1), primarily driven by measurements in the southwestern subtropics,and for the North Atlantic Ocean (40±9 versus 10±2 Tg N yr−1). Moreover, version 2 estimates the N2 fixation rate in theIndian Ocean to be 35±14 Tg N yr−1, which could not be estimatedusing version 1 due to limited data availability. Furthermore, a comparisonof N2 fixation rates obtained through different measurement methods atthe same months, locations, and depths reveals that the conventional15N2 bubble method yields lower rates in 69 % cases compared tothe new 15N2 dissolution method. This updated version of thedatabase can facilitate future studies in marine ecology andbiogeochemistry. The database is stored at the Figshare repository(https://doi.org/10.6084/m9.figshare.21677687; Shao etal., 2022).

Within the Community of Inquiry (CoI) framework, cognitive presence has been central to success in higher education settings. This systematic review examined 24 articles published between 2008- 2020 that empirically analyzed cognitive presence in online courses. We share the patterns that emerged regarding the interplay between teaching and cognitive presence and social and cognitive presence. We also explore how the four phases of cognitive presence--triggering event, exploration, integration, and resolution--were evident within specific instructional activities. We conclude with implications for practice that will be helpful for course instructors and designers seeking to foster greater cognitive presence within their online courses.

Asynchronous video-based discussions have affordances that can address some of the constraints of asynchronous text-based discussions. However, little research has been conducted on the use of asynchronous video-based discussions in online courses. As a result, the purpose of this exploratory study was to investigate students' perceptions of using Flipgrid for asynchronous video-based discussions in fully online courses. We used a cross-sectional survey design to survey 79 students who used Flipgrid in a fully online course. Students overall reported that they liked using Flipgrid, it was easy to use, and that it helped improve social presence. In this paper, we will report the results of our inquiry and implications for research and practice.

The combination of two-dimensional Dirac surface states with s-wave superconductivity is expected to generate localized topological Majorana zero modes in vortex cores. Putative experimental signatures of these modes have been reported for heterostructures of proximitized topological insulators, iron-based superconductors or certain transition metal dichalcogenides. Despite these efforts, the Majorana nature of the observed excitation is still under debate. We propose to identify the presence of Majorana vortex modes using a nonlocal transport measurement protocol originally employed for one-dimensional settings. In the case of an isolated subgap state, the protocol provides a spatial map of the ratio of local charge-and probability-density which offers a clear distinction between Majorana and ordinary fermionic modes. We show that these distinctive features survive in the experimentally relevant case of hybridizing vortex core modes.

This systematic review examines the empirical literature published between 2014 and 2021 that situates artificial intelligence within K-12 educational contexts. Our review synthesizes 12 articles and highlights artificial intelligence's instructional contexts and applications in K-12 learning environments. We focused our synthesis on the learning contexts and the learner-interface interactions. Our findings highlight that most of intelligent systems are being deployed in math or informal settings. Also, there are opportunities for more collaboration to facilitate teaching and learning in domain-specific areas. Additionally, researchers can explore how to implement more collaborative learning opportunities between intelligent tutors and learners. We conclude with a discussion of the reciprocal nature of this technology integration.

Collaboration and teamwork are concepts routinely attributed to organizational success and successful change management. Yet often the details of these collaborative experiences are limited to participants in the team involved. In this case study we highlight how a learning experience architect, as part of an organizational working group, could leverage human performance technology (HPT) principles to lead the analysis efforts surrounding an LMS platform change at a professional training organization. Human performance technology is the study and practice of improving productivity in organizations. This includes designing and developing effective interventions, processes, and methodologies that are ethical, results-oriented, comprehensive, and systemic (West, 2018). This article covers the project's genesis, the project team's creation, and how the analysis work was carried out. The first author's unique access to the subject matter of this case study provides the ability to present the project's analysis phase in the following narrative format. This article's intrinsic case study represents an exploratory inquiry into a single case, as this article's conclusions are inherently limited to its scope. Nevertheless, the article provides evidence that large scale change within organizations requires a balance of effective communication practices and organizational systems thinking.

This design case details the critical design decisions used in the development of an e-learning module library for North Carolina local government officials focused on land use regulations. These modules cover topics from an introduction to land use regulations, to evidentiary hearing conduct guidelines, defining vested rights, and explaining how to adopt and amend an ordinance. This project was in response to the North Carolina League of Municipalities (NCLM) members' increased requests for training in this subject area. This organization requested the assistance of the two faculty members at the University of North Carolina at Chapel Hill School of Government (SOG) who specialize in this content area. Additionally, the professional organization wanted to mitigate risk from cases going to litigation for improper land use decisions. The Target Accomplishment Past Prototype Artifact (TAPPA) Process (Moore, 2016) was used for the module development. This five-step process emphasizes the rapid development of distance education content artifacts in close collaboration with subject matter experts. Between 2013 and 2018, the TAPPA iterative design process guided the development of sixteen modules moving from initial script to finished modules. This design case is relevant for instructional designers who need to develop comprehensive e-learning modules covering complex and often complicated tasks. Examples of design decisions, informed by Clark and Mayer (2016)'s principles of multimedia design, are dispersed through the design case.

The enhanced superconductivity in monolayer FeSe on titanates opens a fascinating pathway toward the rational design of high-temperature superconductors. Utilizing the state-of-the-art oxide plus chalcogenide molecular beam epitaxy systems in situ connected to a synchrotron angle-resolved photoemission spectroscope, epitaxial LaTiO3 layers with varied atomic thicknesses are inserted between monolayer FeSe and SrTiO3, for systematic modulation of interfacial chemical potential. With the dramatic increase of electron accumulation at the LaTiO3/SrTiO3 surface, providing a substantial surge of work function mismatch across the FeSe/oxide interface, the charge transfer and the superconducting gap in the monolayer FeSe are found to remain markedly robust. This unexpected finding indicate the existence of an intrinsically anchored magic doping within the monolayer FeSe systems.

In this paper, I introduce a new term to the online learning lexicon, "mesocredentials," an emerging and transformative approach to integrating massive open online courses (MOOCs) within the higher education system. A mesocredential connects MOOC achievement with academic credit applied to a traditional academic degree. I distinguish mesocredentials from microcredentials based on four requirements: accreditation, delivery modality, academic credit, and flexibility. Through the lens of chaos theory, I explore why mesocredentials are transformative and identify ways they can support adult learners. By linking academic credit to MOOC achievement, mesocredentials create a tangible value for learners and address challenges that MOOCs have experienced in trying to gain a foothold within the higher education landscape. To highlight the potential impact and features of a mesocredential, I examine the MicroMasters® program a registered trademark of The Center for Reimagining Learning, the interim name for edX.

This study assessed a localized academic readiness model that measures academic skills relevant to an occupational program and the institutional context. Enrollment in the program's mandatory gateway course is contingent upon establishing academic readiness either: (1) possess an associate-level or higher degree; (2) achieve placement test scores that permit enrollment in college-level English composition/critical reading; or (3) complete developmental education prerequisites to permit enrollment in college-level English composition/critical reading. Using the gateway course performance for 112 students, the study explored whether any of the model's criterions are significantly related to success in the gateway course and whether there is any significant difference across the three criterions in their relationship to success in the gateway course. The study examined whether there is a significant difference in gateway course success rates between students that had ever been identified as needing developmental education based on a placement test and those that never tested into a developmental education course. Finally, the study examined whether there is a significant difference in gateway course success rates based on age, gender, and race/ethnicity. Results showed that all of the model's academic readiness criterions are significantly related to success in the gateway course and are statistically equivalent to each other in their relationship to success. The results showed that students succeeded at the same rate regardless of their developmental education placement history. Male, Black, and Hispanic students succeeded at a significantly lower rate regardless of how they established academic readiness. Implications and opportunities for future research are discussed.

Focal duodenal necrosis (FDN) is an intestinal disease of egg-layer chickens characterized by multifocal necrosis of the duodenal loop and proximal jejunum. Affected flocks usually have decreased egg weights and drops in egg production. Previous studies have associated this condition with Clostridium perfringens infection. We tried to reproduce FDN by experimental infection of egg-laying chickens using different netB-positive and netB-negative C. perfringens strains, and duodenal homogenate obtained from FDN lesions. Chickens challenged with C. perfringens and/or duodenal homogenate developed duodenitis after challenge. Gross lesions included mucosal erosions, hyperemia, mucosal hemorrhages, and watery intestinal content. Microscopic lesions included mild enterocyte degeneration and necrosis, and mild-to-moderate hemorrhage and lymphoplasmacytic and heterophilic infiltration of the lamina propria. Two netB-positive C. perfringens strains closely related to necrotic enteritis pathogenic strains, by genomic composition, were re-isolated from lesions. Necrosis of intestinal crypts was observed in chickens challenged with duodenal homogenate with or without C. perfringens coinfection. Characteristic microscopic FDN lesions with significant necrosis and loss of villus enterocytes were not reproduced.

The aim of the present study was to examine the effects of attention–deficit/hyperactivity disorder (ADHD) –related psychostimulant use in the context of concussion risk and symptom recovery. Data were obtained from the National Collegiate Athletic Association Department of Defense Grand Alliance Concussion Assessment, Research, and Education (NCAA-DOD CARE) Consortium from 2014 to 2017. Relative to individuals without diagnosed ADHD (i.e., control), both ADHD diagnosis and the combination of ADHD diagnosis and psychostimulant use were associated with a greater risk of incurring a concussive injury. Following a concussive injury, ADHD diagnosis was associated with longer symptom recovery time relative to the control group. However, individuals with ADHD who use psychostimulants did not take longer to resolve symptoms than controls, suggesting that psychostimulants may have a positive influence on recovery. Regardless of time point, ADHD diagnosis was associated with an elevated number of concussion-related symptoms; however, this effect appears mitigated by having used ADHD-related psychostimulants. [ABSTRACT FROM AUTHOR]

As interest in the use of games and gaming elements within learning environments grows, educators and designers may find it easier to account for winning than for losing and failure. This scoping review examines the role of failure and loss within game-based instructional interventions. Because of the varied methods and relatively small number of articles directly addressing the intersection between failure and loss within game-based instructional interventions, a scoping review was undertaken. This review included 14 peer-reviewed articles which explored a range of instructional contexts implementing failure state game mechanics. We identify several key takeaways that indicate how failure state mechanics may have considerable promise in meeting specific instructional goals during game-based instructional interventions. Perhaps most notable in the findings is the delicate relationship between perceived risk of failure relative to instructional utility. We define this relationship with a new term, "unit of failure," which aims to assist practitioners in operationalizing failure and loss in game-based instructional interventions.

This design case discusses key steps taken to establish a virtual makerspace for students enrolled in an online graduate course on informal learning. Two key design decisions are elaborated around (a) the selection of appropriate projects and packaged materials that distance education students can receive by mail to participate in making, and (b) the choice of an online platform for distance education students to document their design processes for assessment purposes and peer interaction and learning. This design case is relevant to a variety of online communities who may wish to engage in maker activities as well as isolated face-to-face communities or individuals who may not have local mentors to support informal making and could, therefore, benefit from online connectivity to an expert or peer support. To promote replication of the design, materials and community tools to support making among geographically dispersed makers are detailed.

This study examined the role motivational dispositions had on completing a massive open online course (MOOC) using identifiable data from 10,726 students who enrolled in an iteration of the HarvardX MOOC, "Super Earths and Life." As part of the course registration process, learners had the option to complete a pre-course survey and self-report information including their level of education, gender and registration motivations. Using these pre-course survey responses, latent profiles linked to learners' course performance were created. Results showed education background, gender, and motivation were all significantly related to students' performance. Furthermore, students with intrinsic motivational dispositions performed better than students with extrinsic dispositions, and females performed better than males.

A growing body of research focuses on what outcomes to assess in makerspaces, and appropriate formats for capturing those outcomes (e.g. reflections, surveys, and portfolios). Linguistic analysis as a data mining technique holds promise for revealing different dimensions of learning exhibited by students in makerspaces. In this study, student reflections on makerspace projects were gathered in 2 formats over 2 years: private written assessments captured in the 3D GameLab gamification platform, and semi-public video-recorded assessments posted in the more social FlipGrid platform. Transcripts of student assessments were analyzed using Linguistic Inquiry Word Count (LIWC) to generate 4 summary variables thought to inform makerspace outcomes of interest (i.e. analytical thinking, authenticity, clout, and emotional tone). Comparative findings indicate that written assessments may elicit more analytical thinking about maker projects compared with less analytical conversation in videos, while video assessments may elicit somewhat higher clout scores as evidence of social scaffolding along with a much more positive emotional tone. Recommendations are provided for layering assessment approaches to maximize the potential benefits of each format, including reflective writing for social spaces, in social groups, and about design processes and procedures.