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Biopolymer-Modified Bentonite Slurry with Gellan Gum for High Salt Resistance in Marine Geotechnical Engineering
Get PDFThe performance of bentonite slurry in submarine tunnel construction is significantly deteriorated by high-salinity seawater intrusion, increasing the risk of excavation face instability. This study investigates the incorporation of the biopolymer gellan gum (GG) into the bentonite slurry, as a high salt resistant and eco-friendly additive. The mechanisms underlying seawater-induced deterioration and GG-imparted salt resistance were analyzed. Results demonstrate that seawater increases the bleeding rate and API (American Petroleum Institute) fluid loss while reducing the apparent viscosity and yield stress of bentonite slurry, thereby compromising its shear-thinning properties. The addition of GG mitigates these negative effects and improves the colloidal stability, rheological properties, and filter cake quality of the slurry. With 1.2% GG, the 24-hour bleeding rate of slurry was reduced from 86.4% to 0%, and a low-permeability filter cake (5.6 × 10⁻⁹ m/s) was rapidly formed, as confirmed by sand infiltration tests. Scanning Electron Microscopy (SEM) analysis revealed that GG re-disperses seawater-induced bentonite platelet aggregates, while Fourier Transform Infrared Spectroscopy (FTIR) results highlight the synergistic effects of cation consumption and gel filling by GG. This study highlights the potential of GG as a sustainable additive for bentonite slurry in marine geotechnical engineering applications.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Beyond Disinformation: Identarian Narratives meet Authoritarian Practices, Lawfare and Marketcraft
Get PDFA stakeholder and policy report based on a knowledge synthesis survey of academic literature and best practices in journalism and public communication.
Preferred Citation: Burchell, K., Ross, J., Tolz, V., Yu, S., Amundson, J., Ding L., Forgacs, H., Kindarji, V., Korotaev, R., Markelov, M., Rodriguez, S., Scarff, S. & Zabalueva, A., with Hutchings S. and Conduit, D. (2025). Beyond Disinformation: Identarian Narratives meet Authoritarian Practices, Lawfare & Marketcraft. A Knowledge Synthesis and Policy Report. Universities of Toronto and Manchester.Disinformation is now the status quo. Beyond the facts of the matter—false claims to be fact-checked or governmental narratives to be debunked—broader forces are shaping our everyday informational landscape. These forces reweight and reorder opportunities to speak, engage, express and represent oneself, limiting our capacity to know, understand, and participate in the world around us. Identity matters as much to this landscape as facts. Repressive legal templates and restrictive economic interventions redefine how we individually or collectively participate in digital life. These changes leave only narrow openings—apertures that permit limited ways of belonging to collective, interpretive communities—while foreclosing so many other possibilities for public life.
By linking these domains of identity, authoritarianism, law and economics, this stakeholder and policy report surveys recent academic literature and journalistic best-practices to demonstrate how the contemporary informational landscape reduces opportunities for local, transnational and global experiences of collective engagement to the strategic needs of governments or the competing commercial imperatives of platform and data economies.“Beyond Disinformation” is funded by the Social Sciences and Humanities Research Council in partnership with UK Research and Innovation Arts and Humanities Research Council as well as a Joint Institutional Partnership between the Universities of Manchester, Melbourne and Toronto. / “Beyond Disinformation” est financé par le Conseil de Recherches en Sciences Humaines en partenariat avec UK Research and Innovation Arts and Humanities Research Council ainsi qu'un partenariat institutionnel conjoint entre les Universités de Manchester, Melbourne et Toronto
Influence of Sloping Ground and Pile Group on Sand Reliquefaction Behavior using Centrifuge Modelling
Get PDFIn the present study free field and pile group models were experimented in a sloping ground using centrifuge modelling. A 2 × 2 pile group model was inserted in Toyoura sand and results were compared with that of free field model ground. Tapered sinusoidal waveform was inputted at a constant 1 Hz shaking frequency, whereas acceleration amplitude and shaking duration for the mainshocks were considered twice that of foreshocks and aftershocks. Two different seismic sequences with six shaking events were imparted to the model grounds to investigate the influence of slope and presence of pile group on sand reliquefaction behavior. The time history responses were recorded in the form of acceleration, excess pore pressure (EPP), bending moment, and lateral displacement and presented. The response indicates that sloping ground was stable under the action of foreshocks, whereas it collapsed during mainshocks, primarily due to liquefaction. The mainshock has transformed the gently inclined sloping ground to levelled ground model. Presence of slope has resulted in higher EPP response and bending moment values compared to levelled ground. GeoPIV analysis and visualization show the flow of sand particles from upside to downside due to lateral spreading at shallow depths that initiated the slope failure.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Robinia pseudoacacia, a nitrogen-fixing tree, facilitates the future growth of neighboring trees in Black Rock Forest
Get PDFTrees that form symbioses with nitrogen (N)-fixing bacteria (N-fixers) have long been thought to facilitate neighbors’ growth by providing new N, but some data do not show facilitation. Two hypotheses to explain the lack of facilitation are that (1) N-fixers may decrease the amount of N they fix over time, reducing the N supply to their neighbors and (2) the effect of facilitation might take longer than the 1-5 y interval of most studies. In this study, we tested these hypotheses with the N-fixing tree Robinia pseudoacacia L. and its non-fixing neighbors, using tree ring N isotopes to estimate past N fixation and tree ring width to estimate past size and growth. Where the isotopes allowed a constrained estimate of N fixation, we did not find support for the first hypothesis: 51% of Robinia’s N came from fixation throughout its 60-y lifespan, with little variation across age. In support of the second hypothesis, we found that Robinia enhanced growth of neighboring trees in the future (up to 14 y) more than in the present. This delayed effect matches the expected timing of facilitation by N-fixers and indicates that single-census studies might underestimate the degree to which N-fixers facilitate forest growth.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Dissolved organic carbon suppresses benthivorous fish biomass by mediating invertebrate resources
Get PDFBenthic invertebrates and benthivorous White Sucker (Catostomus commersonii) were surveyed in eight stratified boreal lakes with DOC concentrations ranging from 3.5 to 9.2 mg . L-1 at the IISD Experimental Lakes Area (IISD ELA) in northwestern Ontario, Canada. Chironomids dominated benthic invertebrate biomass and White Sucker were the dominant fish species. Both White Sucker biomass-catch-per-unit-effort (BPUE) and chironomid biomass were positively correlated with mean light irradiance, with higher biomasses of fish and chironomids occurring in lakes with lower DOC concentrations and a higher proportion of their volume in the photic zone. White Sucker BPUE was also strongly positively correlated with chironomid biomass. A mixing model using stable isotopes indicated that allochthony increased with DOC for both littoral benthic invertebrates and White Sucker. Greater allochthony was also correlated with lower invertebrate biomass and White Sucker BPUE. Our results suggest that DOC suppresses benthivorous fish by reducing the availability of critical food resources. Chironomid biomass appears to decrease with DOC because of lower light penetration that potentially affects primary productivity and the quality of their food resources.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Protecting trees in the urban forest: a systematic review of literature on acts, bylaws, ordinances, and regulations
Get PDFTrees contribute to the livability of cities. To preserve the urban forest, many governments have turned to regulatory mechanisms, ranging from local bylaws and ordinances to state and federal legislation. To understand the history, scope, perspectives, successes, and challenges of disincentive-based tree protection legislation, a systematic review was conducted using PubMD, EBSCOHost, Web of Science, and Scopus. The review, which was not geographically constrained but contained only English-language articles, included 114 publications. The literature highlights that the history of urban forest legislation is long. However, tree protection regulations were popularized more recently, built on years of more general environmental policies. While the adoption processes for tree protection legislation vary across both cities and countries, it is often driven by appreciation of urban forests and led by municipalities with the support of the public and non-governmental organizations. Tree protection legislation defines what trees are to be protected, typically based on size, species, or land use, although cultural or heritage trees are often protected as well. Some tree protection legislation includes replanting clauses and enforcement procedures to increase their effectiveness. The protection of large, culturally important trees and replanting requirements are largely supported by both the public and urban foresters, although support is greater in urban areas. However, whether the legislation actually works is unclear. Conflicting evidence and study limitations preclude direct causal relationships, although areas where tree protection legislation was removed experienced subsequent tree loss. On-going challenges at the local level include underenforcement, conflicting legislation, and underfunded programs. Tree protection legislation is also vulnerable to socio-political changes that prioritize private property rights and development over private tree protection. Amidst widespread urban tree loss, further research that provides a better understanding of the successes of tree protection legislation will help justify their continued use in urban forestry programs globally.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Effectiveness of agricultural BMPs on phosphorus load reduction for the Canadian Lake Erie basin: A literature review
Get PDFLake Erie, the shallowest and warmest of the Great Lakes, has been increasingly threatened by eutrophication and harmful algal blooms affecting economic growth in the region. Excess nutrients, particularly phosphorus, transported with agricultural runoffs have become a major issue of lake water quality. In response to this growing concern over the adverse environmental effects of agriculture, farmers, conservation authorities and governments have worked together to promote and implement best or beneficial management practices (BMPs) in the contributing watersheds that focus on maintaining agricultural activity and farm profitability while protecting the environment. This paper conducted a technical review of BMPs and their effectiveness on phosphorus load reduction from agricultural fields for the Canadian Lake Erie Basin (CLEB). These BMPs include cover crop, conservation tillage, manure incorporation, crop nutrient planning, fragile land retirement, adding organic amendments, reducing soil compaction, controlled tile drain, grassed waterway, vegetative filter strip, riparian buffer, water and sediment control basin, and wetland restoration. Field experiments and modeling studies about BMP effectiveness on phosphorus load reduction from agricultural fields in the CLEB and the Great Lakes region were reviewed and assessed. Findings from other similar geographic regions were also documented for comparison and reference. Because BMPs are site-specific, their phosphorus load reduction effectiveness varied over a wide range in the literature depending upon characteristics of the BMP and local climate, slope, soil type, land use, and land management conditions. Based on the literature review, factors influencing BMP effectiveness were analyzed, and suggestions on research priorities for evaluating BMP effectiveness in the CLEB were provided. This study will benefit decision-makers, watershed conservation authorities, and other stakeholders in estimating phosphorus load reductions from agricultural landscapes and contribute to tracking progress toward achieving Canada’s phosphorus load reduction targets for Lake Erie.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Stretching, Isometrics, and Aerobic Exercise for Decreasing Blood Pressure Post-Exercise: A Randomized Cross-Over Study
Get PDFWe compared stretching, isometrics, and aerobic exercise for effectiveness in decreasing blood pressure post-exercise. Using a randomized crossover design, 5 males and 4 females (21.3y; normotensive) participated in four 30-minute sessions on separate days: static stretching (30s stretches, major muscle groups), isometric exercise, aerobic cycling (75% VO2peak), and control (rest), with blood pressure and heart rate measured before exercise (or rest) and for 60 minutes post-exercise (or rest). Aerobic exercise and stretching decreased post-exercise systolic blood pressure (~10 mmHg each) (pThe presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Bayesian Species Recognition and Abundance Estimation: Unravelling the Mysteries of Salmonid Migration in the Teno River
Get PDFIn Teno River, annual sonar monitoring is used to estimate the abundance of three salmonid species: Atlantic salmon, pink salmon and sea trout. However, the size distribution of these species is partially overlapping making species recognition impossible from plain sonar data. A Bayesian model was developed to tackle this problem and to estimate abundance and migration timing for these three species. The model integrates multiple sources of data including catch, video count, daily average school sizes and expert knowledge. Given the limited catch and video statistics for 2021, the use of school size data and expert knowledge on migration intensity enhanced the estimation when other data sources were unavailable. The model estimated a median of 11.8 thousand Atlantic salmon, 6.6 thousand sea trout and 52.0 thousand pink salmon migrating into the river during 2021. These findings offer a more accurate representation of species distribution, support future conservation and management efforts, and provide a modelling-based solution for distinguishing similarly sized species from sonar counting data.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Measurements of turbulence characteristics in a warped transition
Get PDFTransitions are needed to connect open-channel sections of different shapes and sizes that commonly exist in water supply channels, hydropower channels, irrigation canals and so on. A warped transition (WT) smoothly connects a rectangular with a trapezoidal channel-section and is considered the most efficient transition type with the least flow separation. This paper aims to experimentally investigate the turbulence characteristics in the WT. It reports acoustic Doppler velocimetry measurements of fluctuations in turbulence intensity, kinetic energy and shear stress, as well as of the stationary flow field. The fluctuations are significant and entirely result from the influence of the transition. In the transition, the turbulence features a small jet-like core and reversed flows along one sidewall outside this core; even laterally-averaged velocities have complicated vertical structures. This paper contributes to new benchmark turbulence conditions, useful for assessing the effectiveness of turbulence control devices and validating numerical models of turbulent flow.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author