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Over 50 years ago, a marine estuary was converted to a wastewater stabilization basin for treatment of primarily pulp and paper effluent. As a result, the basin was immediately converted to a "freshwater" environment and subsequently accumulated a thin layer of black, organic-rich sediment containing varying amounts of dioxins and furans, metals, polycyclic aromatic hydrocarbons, and petroleum hydrocarbons. Previous studies on the site have shown that the majority of this contamination in the basin appears to have been contained within this black sediment layer and not migrated to any significant extent into the original underlying marine sediments. The purpose of this study is to examine sediment porewater chemistry changes that have occurred over 51 years of operation of the stabilization basin with the intent of better understanding why contamination has been minimal into the underlying natural marine sediments. Field and laboratory testing is presented to characterize the physical, chemical, and mineralogical sediments in the basin. Porewater chemistry profiles obtained from this work are then used in combination with a one-dimensional contaminant transport model to examine the role of diffusion, sorption, and upward groundwater flux in the porewater profiles found for the sediments. [ABSTRACT FROM AUTHOR]

Facility management maintains building service quality through cycles of condition assessments and rehabilitation. Building components, however, differ in their nature, service lives, deterioration patterns, and textual/visual inspection data. This complicates the condition assessment process and subsequent rehabilitation decisions. This paper proposes a smart condition assessment framework that uses different artificial intelligence (AI) techniques that suit the condition data analysis of different building components. The framework has been applied to a dataset of over 2000 maintenance requests for roof and heating, ventilation, and air conditioning (HVAC) systems across a 600-villa portfolio. To address their varying needs, convolutional neural networks were used on images of roof defects, while enhanced data mining was used on textual data of HVAC systems. Accordingly, work packages of deteriorated components were identified, and a 60-day schedule was developed to repair 203 HVAC units. This research shows how AI can assist facility management with respect to condition assessment, rehabilitation planning, and resource allocation. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although stakeholders' participation in forest management helps overcome problems and conflicts that prevent sustainable solutions, different approaches and nomenclature for similar contents in the literature hinder theoretical progress on the topic. This study organises existing information through a bibliometric analysis of scientific papers from the last 30 years (1991–2021) on sustainable forest management, focusing on the stakeholders' participation. Results demonstrate that stakeholders' participation in sustainable forest management gained relevance from 2017 onwards. Case studies are predominant (66%) and six major trends were identified. The first emphasises a systemic approach to participation. The second updates the community management discussion. The third studies historical problems related to the use of resources, rights, and services. The fourth focuses on regional assessments and studies. The fifth concerns assessment, decision-making, and planning, including issues related to certifications and policies. The sixth discusses innovation related to adaptation, climate change, equity, and resilience. The studies included in this last classification are problem-solving-oriented and seek new forest management. Although important, the role of innovation in stakeholders' participation in sustainable forest management is overlooked, which constitutes an avenue for future research. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Reviews is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Global Navigation Satellite System (GNSS) has emerged as a practical and effective technique for studying slow and steady geodynamic movements, enabling continuous monitoring and precise quantification of deformation over different timescales. In Morocco, a network of GNSS stations has been established, offering valuable insights into tectonic processes. This paper focuses on investigating the geodynamic motion of the northwest Moroccan Atlantic Margin. By utilizing GNSS data, subsidence rates and horizontal velocity fields were determined for the first time, providing valuable information for oil and gas exploration activities. The study reveals an active uplift rate of 1 mm/year and a westward horizontal motion of 2.04 mm/year in the Essaouira segment. The paper presents a case study of the Essaouira–Agadir basin (EAB) onshore segment and investigates the anomalous displacement observed in this region compared to other coastal GNSS stations. Possible explanations for the observed movements include local processes such as salt tectonics and regional northwest–southeast compression related to Africa–Eurasia convergence. We suggest that the anomalous movement detected in this work is due to the regional northwest–southeast compression related to Africa–Eurasia convergence imparting an extrusion of the EAB to the west. This research contributes to a better understanding of the geodynamics in the northwest Moroccan Atlantic margin, thereby providing valuable insights for ongoing efforts in oil and gas exploration. Furthermore, it indicates the continued activity of the Agadir fault, which would exhibit a sinistral wrench movement, thus posing a threat to the city of Agadir and its inhabitants. [ABSTRACT FROM AUTHOR]

Stabilizing piles have been widely used as an effective measure to reinforce slopes. In this paper, a hierarchical response surface method is presented to evaluate the reliability of a pile-slope system efficiently. The suggested method can be used to identify the minimum reliability indexes of different types of failure modes. It can also be used to identify the representative failure modes governing the failure probability of the pile-slope system. This study found that the most critical sliding surface of an unreinforced slope and a reinforced slope is different. It may be nonconservative to design a pile-slope system according to the representative sliding surface of the slope without reinforcements. Even if many failure modes may exist, the reliability index of the pile-slope system is often controlled by several representative failure modes. For the slope examined in this paper, the reliability index of the pile-slope system is controlled by the reliability index of first representative failure mode. The first representative failure mode may vary with the reinforcement ratio, pile length, pile spacing, and location of the piles. The approach presented in this study provides a practical means to quantify the effect of such factors on the design of a pile-slope system. [ABSTRACT FROM AUTHOR]

Syncrude Canada Ltd.'s Base Mine Lake (BML), the first commercial-scale demonstration of an oil sands pit lake, was commissioned in December 2012, following in-pit deposition of fine tailings (FT) between 1995 and 2012. The geotechnical design basis for the FT in BML is that it will consolidate and densify over time, contributing to fines sequestration below the water cap. This paper presents the geotechnical performance of the FT in BML within the context of this geotechnical design basis. The FT has settled from 196.0 to 171.6 Mm3 by 2019, with cumulative settlement varying spatially between 0.3 and 6.7 m. FT settlement is consistent with the expected self-weight consolidation as modeled by finite-strain non-linear consolidation theory, and is reflected as temporal increase in the profiles of solids content and effective stress. Sonar surveying, profile sampling, shear strength, and underwater photography show that the transition of geotechnical properties at the mudline becomes increasingly distinct over time. These observations support the geotechnical design basis for BML and indicate the fines continue to be sequestered below the water cap. [ABSTRACT FROM AUTHOR]

Precommercial thinning could be a valuable tool for climate change adaptation, as it can promote stand diversity while increasing productivity. Softwood and hardwood stands are usually thinned following different methods, and we lack recommendations for application in mixedwood stands. We evaluated the effects of precommercial thinning on the growth and composition of balsam fir (Abies balsameaL.)–birch stands dominated by paper and yellow birch (Betula papyrifera Marsh. and Betula alleghaniensis Britt.), comparing methods and production objectives (systematic release-softwood, systematic release-mixedwood, crop-tree release-mixedwood, and crop-tree release-hardwood) in Québec (Canada). Precommercial thinning increased tree-level and stand-level growth, especially for both birches. Compared to the non-thinned control, thinning increased tree diameter at breast height annual increments by 60%–107%, with similar results among modalities. Thinning changed initial stand composition, but mixedwood production plots composition was similar to that of the control 15 years after treatment. Promoting diversity is often perceived to be made at the expense of wood production. Our results suggest that we can obtain both increased growth and maintain diversity. Precommercial thinning is currently suggested as an adaptation tool that can foster drought resistance. Based on our study, we suggest it could serve another purpose in climate-adapted forest management, that is, maintaining diversity and thus increasing resilience to disturbances. [ABSTRACT FROM AUTHOR]

The paper develops an analytical model based on the force equilibrium for the design of steep slope geosynthetic liner systems to overcome downdrag loads from waste settlement. This analytical model calculates the required tensile stiffness for a high strength/stiffness geotextile (HS-GTX) reinforcement over the GMB to limit the maximum HS-GTX tensile strain to 5% and the maximum GMB strain to 4% on the side slope. The numerical model illustrates the need for reducing the GMB tensile strains for a single GMB liner on a steep landfill slope and confirms that the use of a HS-GTX over the GMB is able to limit the maximum HS-GTX and GMB tensile strains to the acceptable strain levels. The analytical model developed in this paper is a practical tool for preliminary design to limit tensile strains of the HS-GTX and GMB in a steep slope geosynthetic liner system. [ABSTRACT FROM AUTHOR]

The Cambrian pre-salt dolomite sequence in the Tarim Basin is a target zone of great strategic significance for hydrocarbon exploration in the basin. Using the results of the interpretation of 3D seismic data from Lunnan and 2D seismic data covering the whole basin, and based on a synthesis of outcrop data, drilling data, well logs, core data, and thin-section data, and the findings from previous studies, this paper studies the characteristics of the facies of the Middle–Lower Cambrian in the platform area in the Tarim Basin, the formation and evolution of platform margins, and the sedimentary characteristics, lithofacies, and paleogeographic characteristics of the Middle–Lower Cambrian series. Based on the types of lithofacies and the seismic facies analysis, the sedimentary facies of the Middle–Lower Cambrian strata can be classified into the five types. From bottom to top, the Middle–Lower Cambrian have experienced several development stages, including the deposition of continental shelf sediments of the Yuertusi Formation, gently sloping non-rimmed platform margin sediments of the Xiaoerbulake Formation, weakly rimmed platform margin sediments of the Wusongger and Shayilike formations, and strongly rimmed platform margin sediments of the Awatage Formation. In each stage, the platform margin shifted further east relative to its location in the previous stage. Based on these results and previous studies, the lithofacies and paleogeography maps of the Middle–Lower Cambrian in the Tarim Basin are modified, and the implications for hydrocarbon exploration in this area are discussed. [ABSTRACT FROM AUTHOR]

Effective winter road maintenance relies on precise road friction estimation. Machine learning (ML) models have shown significant promise in this; however, their inherent complexity makes understanding their inner workings challenging. This paper addresses this issue by conducting a comparative analysis of road friction estimation models using four ML methods, including regression tree, random forest, eXtreme Gradient Boosting (XGBoost), and support vector regression (SVR). We then employ the SHapley Additive exPlanations (SHAP) explainable artificial intelligence (AI) to enhance model interpretability. Our analysis on an Alberta dataset reveals that the XGBoost model performs best with an accuracy of 91.39%. The SHAP analysis illustrates the logical relationships between predictor features and friction within all three tree-based models, but it also uncovers inconsistencies within the SVR model, potentially attributed to insufficient feature interactions. Thus, this paper not only showcase the role of explainable AI in improving the ML interpretability of models for road friction estimation, but also provides practical insights that could improve winter road maintenance decisions. [ABSTRACT FROM AUTHOR]

Moisture-induced damage has been known as a major premature distresses in asphalt pavement. Numerous review papers have been made to provide the progression in study on moisture damage of asphalt pavement. However, mechanical properties of asphalt mixtures used as a parameter for moisture susceptibility evaluation were not reviewed in detail. To make the review of moisture-induced damage in asphalt pavement more comprehensive, this paper reviews research studies on moisture damage of asphalt pavement in view of mechanical properties as a parameter during the past 50 years. These parameters include tensile strength ratio (TSR), cohesion ratio (CR), dynamic modulus ratio (DMR), resilient modulus ratio (RMR), and shear strength ratio (SSR). TSR and CR are only relevant at bottom of asphalt concrete (AC), while SSR can be used to describe moisture damage at different AC depths. DMR and RMR are concentrated on the impact of moisture damage via performance characteristics of asphalt mixtures. [ABSTRACT FROM AUTHOR]

The road agencies collect and submit weigh-in-motion (WIM) data to the Federal Highway Administration as part of their traffic monitoring program. Therefore, the WIM data should be precise and accurate. One way to evaluate WIM measurement errors is by using the test truck data collected immediately before and after equipment calibration. The limitation of this approach is that the data represent a snapshot in time and may not represent a long-term WIM site performance. This paper presents an approach for estimating WIM system accuracy based on axle load spectra attributes (normalized axle load spectra (NALS) shape factors). This alternative approach allows for characterizing temporal changes in WIM data consistency. The WIM error data collected before and after calibration were related to Class 9 NALS shape factors in the proposed methodology. This paper aims to determine WIM system errors based on axle loading without physically performing WIM equipment performance validation using test trucks. The presented methodology can be used to estimate systematic errors (drift) in the WIM system at any point in time after the equipment calibration. This approach can help highway agencies select optimum timings for routine maintenance and calibration of WIM equipment without compromising its accuracy. The results show that the WIM accuracy for the single axle (SA) and tandem axle (TA) can be estimated with SA and TA NALS shape factors with an acceptable degree of error for bending plate to quartz piezo sensors. Examples are included to demonstrate the application and significance of the developed models. [ABSTRACT FROM AUTHOR]

In this paper, we extend Shaposhnikov et al.'s parity violating the Einstein–Cartan–Holst action by adding to Holst term H, a Proca photon–torsion coupling χpt = 10−24 as computed by De Sabbata, Garcia de Andrade, and Sivaram. The strength of Holst term is obtained, in the case of early universe torsion as, T ∼ 1 MeV. The gravity part is the Planck mass product with the Holst term. The photon mass in this case yields m2γH ∼ 10−69 GeV4. Therefore, in this case, the photon interacts very weakly with spin-torsion matter in Einstein–Cartan (EC) gravity and the strength of the Maxwell–Proca–Holst interaction is much weaker than in the pure gravity sector. For dark photons, this situation changes drastically since a dark photon mass reaches 1.5 GeV, and from this mass and T = 10−3 GeV, one obtains a Maxwell–Proca–Holst strength of 10−6 GeV4, which is now comparable with the gravity sector. Dynamo mechanism competes with the chirality and dissipation by the handness of the magnetic field with respect to the torsion trace vector to regenerate the magnetic field decay. Bombacigno and Mantovani recently found a sign of the Immirzi parameter in the Holst–Nieh–Yan extension of EC gravity. Here, we also find torsion waves for the Immirzi inverse parameter in the sense that this divergence of torsion trace is porportional to the Immirzi field. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Physics is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Physics is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There is an increasing interest in mixed conifer-broadleaf stands as a way to increase the diversity and productivity of managed forests. This study examined the impacts of varying densities of planted broadleaf trees on conifer performance, total stand productivity, and understory plant cover 20 years after stand establishment. The study took place in the Malcolm Knapp Research Forest in Maple Ridge, British Columbia. It used a randomized complete block design to compare treatments containing low, moderate, or high broadleaf densities added to a constant conifer density. Each block contained a conifer-only plot as a control. Conifers were composed of equal amounts of western hemlock, western redcedar, and Douglas-fir. Broadleaves were composed of either red alder or paper birch. We found that conifer volume was significantly lower in most broadleaf treatments relative to the control, due to lower hemlock and redcedar volumes. Douglas-fir, on the other hand, had a higher volume—albeit not significant—in the broadleaf treatments. There were no significant differences in total stand volume between any of the treatments and the control. Shrub cover was significantly higher in the low and high alder treatments relative to the control, but there were no differences in shrub cover between birch treatments and the control. The results suggest that low alder density provides a good balance of conifer yield and understory development. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Physics is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bridge infrastructure assets should be planned, designed, constructed, and operated to account for the physical processes that may occur over their service lives. In ice-affected rivers, this includes the interaction of bridge infrastructure with river ice. Advancements in river-ice science and modelling of ice processes in ice-covered rivers have enhanced the abilities of civil/hydrotechnical engineers to plan, design, and construct bridges in and along rivers with seasonal ice covers. In this paper, an overview is presented of ice-related considerations with respect to bridges. The bottom-chord elevation of the bridge superstructure with respect to water and ice levels, pier design to withstand ice forces, the waterway opening for ice passage, ice-induced scour, and research needs are discussed. However, as outlined in the paper, research on ice loads and passage at bridge sites and on hydroclimatic and ice conditions that led to bridge damage and failure remains needed. [ABSTRACT FROM AUTHOR]

Dr. M. Brock Fenton has been intrigued by the diversity of bats throughout his long career, and has combined his research and photography skills to capture the extensive morphological diversity found across the order Chiroptera. In this paper, we honour Brock's fascination with diversity by conducting a review of the external and internal characteristics of the bat nose, a morphological feature that Brock's photographs have beautifully captured in many bat species. Specifically, we explore variation in form and function of the bat rostrum and its role in respiration, echolocation, and olfaction in bats, with an emphasis on the noseleaves of nasal-emitting echolocators, as well as how turbinate morphology may be impacted by nasophonation. While our review is not an extensive dive into all that is known about bat noses, our goal is to highlight the diversity we see in form across the order Chiroptera while exploring how function has been shaped by selection, particularly in relation to mode of echolocation signal emission. [ABSTRACT FROM AUTHOR]

The package PbIso is a free and open R toolbox for commonly used calculations and plots of Pb–Pb isotope data and for generating Pb evolution models. In this paper, we review Pb isotope systematics and the calculations that are commonly used, such as model age, model source μ (238U/204Pb), time-integrated κ (232Th/238U), and initial Pb isotope ratios. These equations are implemented into R functions in the package PbIso. In addition, functions are provided for generating Pb evolution models, paleoisochrons, and isochrons. This allows users to apply calculations to their data in a straightforward way while providing transparency and flexibility of the calculations used. We have implemented some basic features of the PbIso package into an online shiny R application (see https://shereearmistead.github.io/software/pbiso), which makes it easy for users without any R experience to use these calculations with their own data and to generate plots. We have provided a case study from the Superior Province in Canada, showing how different Pb evolution models can be generated in PbIso and compared to Pb isotope data. [ABSTRACT FROM AUTHOR]