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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]

Consider for a moment the rate of advancement in the scientific understanding of DNA. It is formidable; from Fredrich Miescher’s nuclein extraction in the 1860s to Rosalind Franklin’s double helix X-ray in the 1950s to revolutionary next-generation sequencing in the late 2000s. Now consider the scientific paper, the medium used to describe and publish these advances. How is the scientific paper advancing to meet the needs of those who generate and use scientific information? We review four essential qualities for the scientific paper of the future: (i) a robust source of trustworthy information that remains peer reviewed and is (ii) communicated to diverse users in diverse ways, (iii) open access, and (iv) has a measurable impact beyond Impact Factor. Since its inception, scientific literature has proliferated. We discuss the continuation and expansion of practices already in place including: freely accessible data and analytical code, living research and reviews, changes to peer review to improve representation of under-represented groups, plain language summaries, preprint servers, evidence-informed decision-making, and altmetrics.

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]

RNA interference (RNAi) is a useful tool to assess gene function by knocking down expression of a target gene and has been used successfully in domestic and laboratory organisms. However, the use of RNAi for functional genomics has not fully extended into ecological model organisms in natural environments. Assessment of gene function in the wild is important because gene function can be environmentally and context dependent. Here, we present a case study using RNAi to assess gene function in wild paper wasps Polistes metricus, to test roles for two candidate genes ( NADH dehydrogenase ( NADHdh) and retinoid and fatty acid binding protein ( RfaBp)) in the development of reproductive castes. Previous studies have shown that these genes are upregulated in larvae that become queens compared to workers, but this pattern was reversed in the laboratory, making field-based studies necessary. We orally administered dsRNA to larvae in field colonies and found evidence of a short-term knockdown followed by a compensatory rebound in expression for RfaBp. We also observed the predicted worker-like decrease in lipid stores in NADHdh dsRNA treated wasps, suggesting a possible role for NADHdh in caste development. We discuss our results in the context of challenges for using RNAi for functional genomics in ecological model organisms in the field. [ABSTRACT FROM AUTHOR]

Presents a study that examined the role of papermill sludge in the organic forest carbon cycle of paper products. Prediction on the global production of papermill sludge; Impact of paper production and wastepaper recycling trends on the woody carbon components of sludge; Implications of the organic content and carbon content of sludge for dealing with disposal policy and problems.

Aerated stabilization basins (ASBs) currently account for about one third of the pulp and paper industry's secondary treatment capacity. We surveyed mills with ASBs to analyze design and operating practices. Of the 19 mills that responded, 15 were kraft, reflecting the industry's overall use of ASBs. Biochemical oxygen demand (BOD) and total suspended solids (TSS) loading to the ASBs varied considerably and were factors in biotreatment performance. Problems identified with some ASBs included excessive solids accumulation resulting in the need for frequent dredging, high TSS discharge, and difficulty with nutrient management. Most ASBs have either two or three cells. An important parameter identified for these cells is the benthal settling area. Too small an area results in a higher dredging frequency, with limited nutrient feedback. In general, ASB systems that used the most intensive mixing and aeration in the upstream cells tended to have a smaller benthal settling area, resulting in the need to dredge more frequently. Ideally, some benthal settling should be designed into the upstream cells to allow nutrient feedback where it is needed most. [ABSTRACT FROM AUTHOR]

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.)

A flexible, lightweight, and high conductivity current collector is the key element that enables fabrication of a high-performance, flexible lithium-ion battery. Here, we report a thin, lightweight, and flexible lithium-ion battery that uses graphite papers deposited with nano-sized metallic layers as the current collector, LiFePO4 and Li4Ti5O12 as the cathode and anode materials, respectively, and a PE membrane soaked in LiPF6 as the separator. Using thin, flexible graphite paper as a substrate for the current collector instead of a rigid, heavy metal foil enables us to demonstrate an ultra-thin lithium-ion battery (total thickness including encapsulation layers of less than 250 μm) that also features a light weight and high flexibility. [ABSTRACT FROM AUTHOR]

A novel, simple, and low-cost spray painting technique has been developed for the fabrication of microfluidic paper-based devices. The devices that we developed utilize aerosol spray paint to build hydrophobic barriers and employ a hole puncher to obtain paper-based patterned layers and paper dots without using any specialized instruments (e.g., without a laser cutter). The entire manufacturing process is extremely simple, inexpensive, and rapid, which means that it can be applied broadly. Furthermore, the application of the device to iron detection was demonstrated. A linear relationship between the colour value and the iron concentration was observed from 0 to 0.02 g/L. The developed microfluidic paper-based device for iron detection exhibited a low detection limit (0.00090 g/L), good selectivity, and acceptable recovery. [ABSTRACT FROM AUTHOR]

Presents a study that aimed to determine the levels at which phytosterols are present in Canadian pulp and paper mill effluents (PPME). Description of PPME; Chemicals that form the major fraction of plant sterols in PPME; Processes responsible for the observed removal of plant sterols across the biological wastewater treatment systems.

Eucalyptus globulus subsp. globulus Labill. (Tasmanian Blue Gum), native to southeast Australia, is a benchmark species for the pulp and paper industry. We genotyped 397 trees from 16 populations of E. globulus representing the native diversity in Australia using 24 microsatellite loci. Eight genetically distinct groups were detected, consistent with genetic groupings detected in previous quantitative and molecular studies. A sample of 29 Portuguese individuals was added to help clarify the origin of the Portuguese landrace. The results suggest a southern and eastern Tasmania origin for the Portuguese landrace. This genetic framework will enable researchers to investigate the provenance of individuals of unknown pedigree and assess the levels of representation of E. globulus natural variation in the Portuguese landrace. [ABSTRACT FROM AUTHOR]

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.)

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.)

Comments on the study "Diffusion of Oxygen Through a Pulp and Paper Residue Barrier," which discussed the use of deinking residues to create an oxygen barrier. Complexity in using diffusion equations; Expression of Fick's laws based on equivalent porosity; Comment on the use of specific solutions to Fick's laws to evaluate the flux and controlling parameters.

A waste-derived paste of a mixture of paper sludge and tire derived aggregate (TDA) was investigated for daily cover application in municipal solid waste (MSW) landfills. The use of earth materials as daily covers not only consumes valuable landfill space, but also creates a series of operating issues. In this study, an experimental testing program was undertaken with the goal of evaluating the mechanical behaviors of the paste based on the findings of the index properties, compressibility, hydraulic conductivity, stress-induced deformation, stress–strain response, and shear resistance of the materials. The mechanical behaviors of the individual TDA, the sludge, as well as the mixture of the two, were evaluated. When compared to traditional soil covers, the proposed paste was: (i) 2–3 times lighter in weight; (ii) at least two orders of magnitude more impermeable; and (iii) comparable in shear resistance. It was also found that with the addition of TDA to the sludge, the shear strength of the paste was improved considerably. The reinforcing mechanisms were explored and quantified, suggesting an optimal TDA content of about 55% by weight. The results from this study indicate that the proposed paste has mechanical characteristics that are desirable for a potential landfill daily cover. [ABSTRACT FROM AUTHOR]

This study investigated the use of bark and combined paper sludge to develop a suitable plant growth substrate and to establish a vegetation cover on bark-covered land. Field experiments were established to determine the best plant growth medium, plant mixtures, and fertilization program. The best soil cover consisted of 2.5 cm of combined paper sludge on top of 2.5 cm of black bark. On this soil cover, the Savoureux mixture in combination with birdsfoot trefoil (Lotus corniculatus L.), Lab02 in mixture with MR77, and birdsfoot trefoil in mixture with bromegrass (Bromus inermis L.) gave good vegetation growth and yields. For birdsfoot trefoil over all soil covers, the phosphorus and potassium fertilizations were required at 140 kg P2O5/ha and 160 kg K2O/ha, respectively. These results suggest that combined paper sludge and black bark can be used as topsoil to favor plant establishment on bark-covered land. [ABSTRACT FROM AUTHOR]

The kinetics of the spontaneous, proton- and AlIII-catalysed hydrolyses of the C1—O4′ bond in 1,5-anhydrocellobiitol have been measured at elevated temperatures (125.0–220.0 °C). Data for the first two processes extrapolate to the expression k = (8.6 ± 2.1 × 10–16) + (1.4 ± 0.2 × 10–9-pH) s–1 at 25 °C. These room-temperature figures were used to model cellulose depolymerization by the af Ekenstam equation. The spontaneous process is too slow to contribute to loss of paper strength on aging, and even the acid-catalysed process is significant only below ~pH 4.0. However, the spontaneous hydrolysis readily accounts for the reduction of cellulose degree of polymerization (DP) during alkaline (e.g., kraft) pulping of cellulose fibres. Efficient electrophilic catalysis by AlIII was observed at 150.0 °C in 0.1 mol/L succinate buffers of room temperature pH 3.05 and 3.35 (k2 = 8.1 ± 0.4 × 10–3 and 4.2 ± 0.2 × 10–3 (mol/L) –1 s–1, respectively). The apparent activation energy of the AlIII-catalysed process was 31 ± 4 kJ mol-1, lower than that of the proton-catalysed path, suggesting the electrophilic catalysis increases in importance as the temperature approaches ambient. Consequently, it appears that the culprit in the impermanence of “rosin-alum” -sized paper is AlIII, directly acting as a Lewis acid, not the AlIII hydration sphere as a Brønsted acid. Conservation measures should either address this or be generic (e.g., low-temperature storage). [ABSTRACT FROM AUTHOR]

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.)

This article was written to serve as an introduction to this issue of the Canadian Journal of Chemistry that honors the contributions to chemistry of Professor D.R. Arnold. It summarizes the observations reported in a communication that appeared in the Journal of the American Chemical Society 30 years ago in June 1973. This historically important communication laid the foundation for his program on the photochemical generation and reactivity of radical ions in solution and also served as a guide for a developing area of interest of many other research groups. [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 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.)

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]

The announces the winners of 2018 Best Paper Award including Chris E. White, Sandra M. Barr, and Ulf Linnemann given jointly by Canadian Science Publishing and Geological Association of Canada.

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]

Deinking by-product (DBP), a cellulose-rich by-product produced in the early stages of the paper recycling process, has been used as alternative material for the construction of cover systems for municipal waste disposal facilities and acid-producing mine residues. Because of the high organic content of this material, covers constructed with it are susceptible to biodegradation and, thus, to changes in their properties with time. With the goal of identifying the biodegradation parameters that could influence the long-term behaviour of DBP covers, an experimental laboratory program was developed and a series of 15 samples of DBP were monitored in biodegradation tests for 400 d. Periods of intermittent water percolation allowed for collection of leachate. The evolution of gas and leachate production was monitored in terms of quality and quantity. According to the results obtained, the hydraulic and geomechanical properties of importance for a cover do not seem to be adversely affected by the level of biodegradation of the DBP or by mass loss. [ABSTRACT FROM AUTHOR]

The article presents abstracts of papers published in "Canadian Geotechnical Journal" which have been selected for the 2016 R.M. Quigley Awards, including "Behavior of a group of energy piles" by Mimouni and Laloui, "Ageing of exposed geomembranes at locations with different climatological conditions" by Kerry Rowe and Ewais, and "Classification and quantification of downslope erosion from a geosynthetic clay liner (GCL) when covered only by a black geomembrane" by Brachman and others.

The article announces that Tiffani A. Fraser and Matt P. Hutchison won the 2017 Best Paper Award from the Canadian Science Publishing and the Geological Association of Canada.

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 article announces the awarding of the journal's R. M. Quigley Award to scholar P. K. Robertson, as well as honourable mentions for the award to scholars including Louis Le Pen, David Milne, and C. W. W. Ng.

The article announces that the GAC–CSP Canadian Journal of Earth Sciences Best Paper Award for 2016 has been presented to Richard A. Glen and colleagues for their study related to different styles of non-collisional orogens and implications for crustal growth.