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Spatial and Temporal Trends of Dissolved Polybrominated Diphenyl Ethers and Non-BDE Flame Retardants in the Aquatic Environment across Countries
No full textMeasuring dissolved concentrations of polybrominated diphenyl ethers (PBDEs) and non-BDE flame retardants on a global scale provides critical insights into the effectiveness of the Stockholm Convention. In the present study, we deployed passive sampling devices at 43 seawater and freshwater sites covering 21 countries from 2016 to 2020. The detection frequencies were 20–94% for BDE congeners and 33–42% for dechlorane plus, higher than those (0–20%) for other target compounds. The median concentrations of dissolved Σ9PBDE (sum of BDE-28, -47, -66, -85, -99, -100, -153, -154, and -183) were 0.28 and 0.64 pg L–1 in seawater and freshwater, respectively. The concentrations of dissolved Σ9PBDE, along with published data, slightly increased before 2016 and remained steady from 2016 to 2018, indicating delayed effects of the global phaseout of technical Penta- and Octa-BDEs. The log-transformed concentrations of individual BDE congeners were better correlated with regional gross domestic product than with population density. The potential ecological risk of BDE-47 was low, and there was a lack of key risk indicators for other compounds. The present study documented the delayed response of the aquatic environment to the regulatory actions on reducing PBDE emissions.
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Jammed disks of two sizes in a channel: Segregation driven by steric forces
No full textDisks of two sizes are confined to a long and narrow channel. The axis and the plane of the channel are horizontal. The channel is closed off by pistons that freeze jammed microstates out of loose disk configurations, agitated randomly at calibrated intensity and subject to moderate pressure. Disk sizes and channel width are such that under jamming no disks remain loose and all disks touch one wall. The protocol permits disks to move past each other prior to jamming, which facilitates randomness in the sequence of large and small disks. We present exact results for the characterization of jammed macrostates including volume and entropy for given fractions of small and large disks as functions of energy parameters which depend on the jamming protocol. Our analysis divides the disk sequence of jammed microstates into overlapping tiles out of which we construct 17 species of statistically interacting quasiparticles. Jammed macrostates then depend on the fractions of small and large disks and on a dimensionless control parameter inferred from measures for expansion work against the pistons and intensity of random agitations. Two models are introduced for comparison of key technical aspects: one model emphasizes symmetry and the other mechanical stability. We distinguish regimes for the energy parameters that either enhance or suppress mixing of disk sizes in jammed macrostates. The latter case, if realizable, is a manifestation of grain segregation driven by steric forces alone, without directional bias.
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Evaluation of an Active Control, Constant Normal Stiffness Apparatus for Improved Evaluation of Shaft Friction in Micropiles in the Offshore Environment
No full textThere is increasing interest in using micropiles as a foundation type for floating offshore wind farms in deep water. Contrary to onshore projects, proof load testing of micropiles in the offshore environment is extremely difficult if even feasible, and as a result, better capacity prediction approaches are required. A key improvement would be incorporation of constant normal stiffness boundary conditions in the evaluation of shaft resistance of small-diameter grouted micropiles. The objective of this study is to present the results of a newly developed, active control system for performing constant normal stiffness tests on sand. A laboratory testing program of monotonic CNS tests on Monterey sand was performed in which relative density, soil spring stiffness, and initial normal effective stress were varied. The ability of the control system to maintain constant normal stiffness during shear was found to be excellent, and test results on both dilative and contractive samples demonstrated consistent trends of shear strength and changes in both shear band thickness and normal effective stress
Implicitly developing young learners’ digital and media literacy through technology-enhanced tasks in primary EFL classrooms
No full textThis article presents a research project that explored the perspectives of preservice and in-service primary English language teachers on the use of technology-enhanced tasks to support young learners’ development of oral communicative competence in the diverse primary English as a foreign language (EFL) classroom. The classroom-based research involved the implementation of technology-enhanced tasks in three different projects in three different primary schools. The projects aimed to support young learners in developing their speaking competence in the target language. Data were collected through classroom observation, teacher training, videography of lessons, and participant interviews. Reflexive thematic analysis was used to analyse the data. The results suggest that participants perceive technologyenhanced tasks not only as well suited to supporting children’s development of oral communicative competence, but also as implicitly promoting children’s digital and media literacy. These findings may point to a new avenue of research into teachers’ perspectives on the use of digital technologies in primary EFL classrooms. The article highlights that the use of technology-enhanced speaking tasks can be a subtle way of promoting digital and media literacy in young EFL learners
The Library Instructor as Learner: A Survey of Reflective Teaching Practices in US Academic Libraries
No full textReflective practice provides library workers with a critical opportunity to examine professional experiences, question assumptions and approaches, explore new perspectives, and develop innovative solutions to existing problems. When applied to instruction as reflective teaching, this practice better situates library instructors to meet the evolving needs of twenty-first-century library users. This research study explores how library workers engage with reflective teaching in academic libraries across the United States. A survey was distributed to academic library communities, and a total of 153 responses were collected. While 92% of respondents reported participating in reflective teaching practice in a variety of instructional contexts, results indicated that respondents have utilized a broad range of methods for reflection and experienced numerous benefits and barriers. These diverse experiences suggest that library instructors see value in reflective work and would benefit from greater training and opportunities to participate in this practice
Financial resilience: A scoping review, conceptual synthesis, and theoretical framework
Full text linkPurpose: Financial resilience is becoming increasingly important in socioeconomic environments, yet research on the topic remains in its early stages and is subject to debate. This study aims to provide an overview of the existing literature on financial resilience and develop a heuristic map.
Methodology: A four-step scoping review was conducted to extract data on research features, measures, determinants, outcomes, and definitions from 44 empirical studies on financial resilience across five academic databases.
Findings: Most studies have examined financial resilience over the past five years utilizing cross-sectional secondary data from specific countries. The included studies have used various resources to assess financial resilience and investigate its determinants and outcomes across socioeconomic, psychological, and situational domains. Financial resilience is newly defined as a financial coping capability that encompasses both static performances and dynamic processes within human agency and environmental structure, enabling people to respond to and recover from adverse situations. This coping capability definition provides a comprehensive and positive perspective, addressing limitations in previous resource-based, behavior-based, and vulnerability-oriented definitions. The long-term process of financial resilience consists of three dynamic stages leading to positive adaptation. An integrative framework is proposed to outline several propositions and pathways relevant to proximal dynamics, distal mechanisms, and evidence-based interventions for financial resilience. Four priority areas are suggested to enhance theories, topics, contexts, and methods in future financial resilience research.
Originality: This study provides an original synthesis of financial resilience and theoretical insights for researchers across various disciplines. Financial service providers, practitioners, and consumers may benefit from this study for promoting sustainable wealth management and overall well-being
