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A new esterase gene est906 was identified from paper mill wastewater sediments via a function-based metagenomic approach. The gene encoded a protein of 331 amino acids, that shared 86% homology with known esterases. Based on the results of multiple sequence alignment and phylogenetic analysis, it was confirmed that Est906 contained a characteristic hexapeptide motif (G-F-S-M-G-G), which classified it as a lipolytic enzyme family V protein. Est906 displayed the highest hydrolysis activity to ρ-nitrophenyl caproate (C6), and its optimal temperature and pH were 54 °C and 9.5, respectively. Additionally, this enzyme had good stability under strong alkaline conditions (pH 10.0–11.0) in addition to moderate heat resistance and good tolerance against several metal ions and organic solvents. Furthermore, a specific nucleic acid aptamer (Apt1) bound to Est906 was obtained after five rounds of magnetic bead SELEX screening. Apt1 displayed high specific recognition and capture ability to Est906. In conclusion, this study not only identified a new esterase of family V with potential industrial application by metagenomic technology but also provided a new method to purify recombinant esterases via nucleic acid aptamers, which will facilitate the isolation and purification of target proteins in the future. [ABSTRACT FROM AUTHOR]

Stable isotope analysis of a novel combination of carbon and nitrogen pools traced inputs and processing of primary- treated (PE) and secondary-treated effluent (SE) from a paper and pulp mill (PPM) in a temperate Australian estuary. Distinct carbon stable isotope ratios of dissolved organic carbon (DOC) near the PPM outfall indicated large PE and reduced SE inputs of DOC. DOC was remineralized to dissolved inorganic carbon regardless of season, but rates were lower in winter. PE discharge in winter elevated DOC concentrations along much of the estuary. Distinct stable isotope ratios confirmed particulate organic matter (POM) input from PE and SE to the water column and into the sediment This was relatively localized, indicating rapid POM settlement regardless of season SE discharge increased nutrient inputs and enhanced algal productivity, particularly in summer when chlorophyll-a concentrations were elevated throughout the estuary. SE discharge reduced pCO2 from levels associated with PE discharge. However, the estuary remained heterotrophic as subsequent respiration or decomposition of algal material offset reductions in PPM organic matter input. The influence of the PPM was apparent throughout the estuary, demonstrating the ability of anthropogenic inputs, and changes to these, to affect ecosystem functioning. [ABSTRACT FROM AUTHOR]

Abstract: In this study geno-toxicity analysis along with effluent treatment was taken up to evaluate the efficiency of biological treatment process for safe disposal of treated effluent. Four fungi were isolated from sediments of pulp and paper mill in which PF4 reduced colour (30%) and lignin content (24%) of the effluent on 3rd day. The fungal strain was identified as Emericella nidulans var. nidulans (anamorph: Aspergillus nidulans) on the basis of rDNA ITS1 and rDNA ITS2 region sequences. The process of decolourization was optimized by Taguchi approach. The optimum conditions were temperature (30–35°C), rpm (125), dextrose (0.25%), tryptone (0.1%), inoculum size (7.5%), pH (5) and duration (24h). Decolourization of effluent improved by 31% with reduction in colour (66.66%) and lignin (37%) after treatment by fungi in shake flask. Variation in pH from 6 to 5 had most significant effect on decolourization (71%) while variation in temperature from 30 to 35°C had no effect on the process. Treated effluent was further evaluated for geno-toxicity by alkaline single cell gel electrophoresis (SCGE) assay using Saccharomyces cerevisiae MTCC 36 as model organism, indicated 60% reduction. [Copyright &y& Elsevier]

Abstract Rapidly detecting trace levels of organic contaminants in complex mediums is a great challenge for mass spectrometry analysis. Especially in dealing with large quantities of soil samples, the laborious sample pretreatment process is exhausting and time consuming. Here, a simple method for quickly identifying and quantifying tetrabromobisphenol A (TBBPA) in soils and sediments has been developed via paper spray ambient mass spectrometry coupled with a stable isotope internal standard technique in this study. The soil and sediment extracts, spiked with a certain amount of 13C 12 -TBBPA (Ring-13C 12), are directly loaded and separated on chromatographic paper, sprayed and ionized by a high negative voltage, and ultimately analyzed by mass spectrometry without purification and chromatography separation processes. Data acquisition for each test can be finished within 1 min. In the quantification of TBBPA, a linear range of 0.1–100 µg L–1, a limit of detection of 0.039 µg L–1 and a relative standard deviation (c = 1.0 µg L–1, n = 5) of 5.3% are obtained. The spiking recoveries range from 90.4% to 101.1% for analyzing ten soil and sediment samples (0.012–30.14 µg g–1 dw), suggesting that the method should be a promising strategy for rapidly detecting organic pollutants in soils and sediments. Graphical abstract A simple method for quickly identifying and quantifying tetrabromobisphenol A (TBBPA) in soils and sediments has been developed via paper spray ambient mass spectrometry coupled with a stable isotope internal standard technique. fx1 Highlights • Tetrabromobisphenol A in soils and sediments can be rapidly and precisely detected. • Purification and chromatography separation processes are not needed. • As low as 0.039 µg L–1 of TBBPA (limit of detection) can be detected. • High-throughput analysis of soil and sediment samples is achieved. [ABSTRACT FROM AUTHOR]

Effluents from paper mills are highly toxic and are a major source of aquatic pollution. In this study, we collected water and sediment samples to examine the microbial communities using denaturing gradient gel electrophoresis and identified bacterial taxa greatly affected by paper mill pollution using next-generation sequencing data. Our results indicated that bacterial communities in downstream sediments were similar to those in paper mill discharge sites, indicating obvious effects of pollution, while bacterial communities in downstream water samples showed similar profiles to those in upstream sites, both being quite different from the bacterial communities in paper mill discharge sites. This was possibly because of the short contact period. In addition, bacterial communities in the estuary were quite different from those in other water and sediment samples, which was owing to the special habitat type. Considering the storage of paper mill pollutants in sediment and the significant effect on shifts in bacterial communities, we selected Clostridia and Epsilonproteobacteria at the class level and Fusibacter and Desulfobulbus at the genus level as bacterial indicators of paper mill pollution. To monitor the remediation of polluted aquatic environments, we propose Sphingobacteria , Alphaproteobacteria , Actinobacteria , Subdivision3 , Planctomycetacia and Verrucomicrobiae at the class level and Bacillus , Steroidobacter , Nocardioides , Terrimonas , Pirellula and Methylibium at the genus level. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzo-p-dioxins and dibenzofurans in the sediments of aquatic systems are a persistent global problem that poses serious health risks. Identifying the sources of dioxins in natural water systems and the extent of their contributions to observed sediment concentrations is important from a health advisory and mitigation perspective. This paper proposes novel distribution-based qualitative and quantitative methods as source apportionment techniques and alternatives to conventional source attribution methods. Using sampled data, air, runoff, industrial effluent, and industrial paper and pulp wastes were identified as four distinct dioxin contributors to concentrations found in the sediments of the test bed region: the Houston Ship Channel-San Jacinto River-Galveston Bay (HSC-SJR-GB) estuarine system that also includes 2 Superfund sites with dioxin contamination. Two qualitative methods, the Kullback–Leibler divergence (K-L divergence) and the Bhattacharya measure (BM), and a quantitative method, the L2 norm, were used to investigate the spatial and temporal sourcing patterns of dioxins in the system sediments. The results indicated a global contribution from air and runoff sources across the estuarine system and over time with more localized impacts of the Superfund sites and the industrial sources. The results using the developed methodologies were compared with the output from the more conventional positive matrix factorization (PMF) method. Statistically significant correlations were observed among source contributions from the proposed methods and the PMF method, with Spearman's ρ ranging between − 0.596 to − 0.963 and 0.652 to 0.719, demonstrating the utility of the sourcing approaches used in the study. Additionally, the proposed methods were found to be rigorous in terms of elucidating spatial and temporal changes in the sourcing of dioxin to the estuary, indicating their suitability for use for other contaminants and other estuarine systems. [ABSTRACT FROM AUTHOR]

Pulp and paper wastewater (PPW) contains significant concentrations of phytosterols, suspected of inducing endocrine disruption in aquatic species. Aerated stabilization basins (ASBs) are commonly used for the treatment of PPW, but phytosterol removal varies among treatment systems. The objective of this study was to better understand the removal processes and biotransformation of phytosterols within an ASB treatment system fed with untreated PPW. PPW settled solids and supernatant fractions showed that phytosterols are primarily associated with settleable solids, which carry phytosterols to ASB sediment where anoxic/anaerobic conditions prevail. Bioassays with supernatant and settled PPW fractions of the raw wastewater conducted under aerobic and anaerobic conditions, respectively, showed that solids disintegration and hydrolysis results in phytosterol release in ASBs. A simulated ASB, fed with PPW and operated for 2.4 years at three hydraulic retention times (HRTs; 22.2, 11.1 and 5.6 d) with total phytosterol and solids loading rates from 10 to 42 μg/L-d and 44–178 mg/L-d, respectively, was used to determine the steady-state effluent quality and sediment characteristics. Although effluent COD and phytosterol concentrations were relatively low and stable (84–88% total COD removal; 82–94% total phytosterol removal) across the range of HRTs tested, sediment COD and phytosterol concentrations increased with increasing loading rate. On average, 51% of the phytosterols entering the ASB were removed via biotransformation, 40% were retained in the sediment, and the remaining 9% exited with the effluent. This study demonstrates the role of sediment as a source of phytosterol release in ASBs and highlights the importance of HRT and the PPW characteristics for predicting phytosterol fate in ASBs. [ABSTRACT FROM AUTHOR]

New data on the concentration and spatial distribution of the benz(a)pyrene and polycyclic aromatic hydrocarbons in bottom sediments in the testing area of the Baikal Pulp and Paper Plant (BPPP) waste water discharge in 1981-1988 and 2010 are presented in this paper. The bottom sediments in this section of the lake are strongly polluted with polycyclic aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

Fluid circulation within low-permeability basement rocks has been proposed to occur beneath many sediment- hosted mineral deposits, in some cases contributing substantial metals or sulfur to the deposits in overlying cover sequences. However, mechanisms proposed for fluid transport and mass transfer within and through basement rocks are diverse, some models appealing to thermal circulation but others appealing more to deformation- or topography-driven flow. We address some of these issues here by a series of numerical models designed to compare and then couple thermally and mechanically driven fluid flow (and incorporate temperature-dependent fluid properties), starting with generic problems and then using a simulation of coupled deformation, heat transfer, and fluid flow that may be applicable to the formation of Mount Isa-style Pb-Zn ores and other extension-related basinal deposits. Results from deformation-only models show that downward penetration of near-surface fluids into relatively low permeability basement rocks may occur along fault zones at high strain rates during extension, because local deformation rates may exceed the capacity for fluid to move through the basement rocks due to their low permeability, leading to periods of underpressure. For our thermal fluid-flow models, in the absence of deformation and with elevated basal heat flows, large differences in basement and cover permeability tend to restrict thermal convection to the permeable units. Downflow into low-permeability basement may occur by a reduction of the permeability of cover sequences, because larger convection cells are possible as permeability approaches common, optimal values throughout the rock mass. The normal reduction in porosity and permeability of cover sequences with burial may thus lead to progressively deepening convection ceils and an enhanced potential for extraction of components from basement rocks. Long-lived, stable convection is generated with ≤2 order of magnitude permeability difference between basement and cover. Such convection has the potential to lead to near-surface mineralization (e.g., sediment-hosted syngenetic or diagenetic deposits), particularly if an initial overpressure stimulates convection cells toward upflow along basin-bounding faults. These models also serve to indicate the inadequacy of models that do not incorporate therma l dependencies of fluid viscosity and density, because the upward fluid velocity generated by buoyancy is of the same order of magnitude as the downward fluid velocity generated by extension-related underpressure in models that do not incorporate these p roperties. In numerical models of coupled deformation, heat transfer and fluid flow in which high basal heat flow is coupled with extensional deformation, the effects of the deformation dominate flow regimes, rather than the thermal structure. A model with initial heating and fluid flow established large convection ceils with basement fluid circulation, prior to deformation being incorporated. The convection cells are effectively destroyed by extension at geologically reasonable strain rates around 10-14s-1, with surface fluids driven downward and meeting remnant s of the decaying convection deep in the system.& [ABSTRACT FROM AUTHOR]

Purpose: Numerous sites contaminated with fiber emissions from pulp and paper industries are found in coastal areas of the Baltic Sea, but there is limited knowledge about the magnitude of dispersal of persistent organic pollutants (POPs) from these anthropogenic, organic-rich sediments called fiberbanks. The aim of this study was to quantify and compare different POP dispersal pathways from such fiberbanks. Dispersal mechanisms studied included abiotic and biotic routes (dissolved in water, particle-bound, and bioaccumulation). Materials and methods: Contaminated fibrous sediments located in Ångermanälven River estuary in north-eastern Sweden were studied in sediment types representing different fiber content (i.e., fiberbanks, fiber-rich sediments, and less fiber impacted sediments). Sediment-to-water fluxes of dissolved contaminants (polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and dichlorodiphenyltrichloroethane (DDT)) were measured in situ using benthic flux chambers. Particle resuspension was measured by sampling bottom water, before and after disturbing the sediment surface. Benthic biota was collected to determine the body burden of contaminants and to determine biota-pore water accumulation factors (BAFPW) and biota-sediment accumulation factors (BSAFs). In addition, concentrations of dissolved POPs in the water column were measured in field using passive samplers. Instrumental analysis was performed using gas chromatography coupled to a triple quadrupole mass spectrometer (GC-MS/MS). Results and discussion: The flux of dissolved Σ20PCBs was approximately two times higher from one of the investigated fiberbanks (3.4 ng m− 2 day− 1) compared to the other. The average particle burden of PCBs was also higher at this fiberbank after artificial disturbance (15 ng g−1 particle), which indicates that larger amounts of contaminants are likely to disperse via particle resuspension from this site compared to the other fiberbank (4.8 ng g− 1 particle). The difference might be associated with a layer of recently settled minerogenic material that covers one of the fiberbanks, which probably functions as a protective barrier. The lack of benthic biota implies that contaminant release by bioturbation is negligible in the studied fiberbanks. However, benthic biota from fiber-rich sediment showed bioaccumulation and biomagnification of contaminants. Conclusions: The importance of diffusive flux from fiberbanks under undisturbed conditions became apparent when the different dispersal pathways were quantified. However, no dispersal pathway could be judged as irrelevant, since even under undisturbed conditions, advective particle transport was significant. Additionally, the uptake by biota and trophic transfer can be considerable. Quantification of dispersal routes and understanding of the relative importance of various pathways is critical for proper risk assessment and management of contaminated sediments. [ABSTRACT FROM AUTHOR]

This paper presents an assessment of recycling of thermally treated fluvial sediments as a supplementary cementitious material (SCM). Different calcination treatments were conducted with temperatures ranging between 450°C and 950°C. For each calcined sediment, a detailed characterization was carried out. Subsequently, blended cements containing 25% calcined sediments (CS) were prepared and tested, including portlandite consumption, hydration kinetics, and compressive strength development (41 and 52 MPa at 7 and 90 days, respectively). The results showed that blended cement based on CS at 750°C provided the most favorable hydration kinetics and the highest compressive strength. An optimization design of experiment was followed to maximize the substitution rate of CS. The resulting multivariable function suggests a replacement rate up to 20% to produce a blended cement equivalent to CEM II 52.5 N, and up to 30% to produce a cement equivalent to CEM II 42.5 N. The reported technoenvironmental findings corroborate the use of CS as SCMs and motivate future research on their effect on concrete properties. [ABSTRACT FROM AUTHOR]

In recent years, the Journal of Palaeogeography (Chinese Edition and English Edition) continually received manuscripts, in which some authors are from China and some are from Pakistan, Lithuania, Morocco, South Africa, etc. The authors of these manuscripts, according to the viewpoint and method of Miall's paper (1985), selected rocks from each bed in the clastic sections of their study areas and induced some rock types, such as conglomerates, sandstones and fine-grained stones, and considered them as lithofacies. It does not conform to the definition of lithofacies. I wrote some papers, i.e., Feng (2018, 2019, 2020), to point out the problems and hope that the authors worldwide, especially Chinese authors, will not continually cite, spread and follow Miall's paper (1985) viewpoint and method blindly. Prof. Miall is the first person who considered rocks (in fact, the sediments) as lithofacies and proposed a facies analysis method. His viewpoint and facies analysis method confused the definition of facies and facies analysis method. My current paper is a special article to discuss the principal problems of Miall's paper (1985), i.e., he considered the sediments as lithofacies and utilized lithofacies to analyze facies, but not to discuss the contributions and less strictness of architectural elements of his paper. Here, I have to declare that the facies in my current paper is the facies of sedimentary petrology, but not of other geological disciplines, such as igneous petrology, metamorphic petrology, palaeontology, stratigraphy, geophysics, geochemistry. Certainly, the definitions of facies and lithofacies are controversial. My current paper will adhere to the policy of "A hundred flowers blossom and a hundred schools of thought contend". I hope that through academic discussions, contends and geological practice, these problems will be solved gradually. [ABSTRACT FROM AUTHOR]

Arnold, L. J., Roberts, R. G., MacPhee, R. D. E., Haile, J. S., Brock, F., Möller, P., Froese, D. G., Tikhonov, A. N., Chivas, A. R., Gilbert, M. T. P. & Willerslev, E. 2010: Paper II - Dirt, dates and DNA: OSL and radiocarbon chronologies of perennially frozen sediments in Siberia, and their implications for sedimentary ancient DNA studies. Boreas, Vol. 40, pp. 417-445. 10.1111/j.1502-3885.2010.00181.x. ISSN 0300-9483 The sedimentary ancient DNA ( sedaDNA) technique offers a potentially invaluable means of investigating species evolution and extinction dynamics in high-latitude environments. An implicit assumption of the sedaDNA approach is that the extracted DNA is autochthonous with the host deposit and that it has not been physically transported from older source deposits or reworked within the sedimentary profile by postdepositional mixing. In this paper we investigate whether these fundamental conditions are upheld at seven perennially frozen wetland sites across the Taimyr Peninsula and coastal lowlands of north-central Siberia. Optically stimulated luminescence (OSL) and radiocarbon (C) dating are used to constrain the ages of both the inorganic and organic fractions of perennially frozen deposits from which sedaDNA of extinct and extant species have been recovered. OSL and C age/depth profiles, as well as single-grain equivalent dose (D) distribution characteristics, are used to assess the stratigraphic integrity of these sedaDNA sequences by (i) identifying the presence of primary or reworked organic and inorganic material, and (ii) examining the types of depositional and postdepositional processes that have affected specific sedimentary facies. The results of this study demonstrate that even though DNA preservation and stratigraphic integrity are commonly superior in perennially frozen settings, this does not, in itself, guarantee the suitability of the sedaDNA approach. The combined OSL and C chronologies reveal that certain perennially frozen sites may be poorly suited for sedaDNA analysis, and that careful site selection is paramount to ensuring the accuracy of any sedaDNA study - particularly for 'latest appearance date' estimates of extinct taxa. [ABSTRACT FROM AUTHOR]

In this paper, a method for augmenting samples of side-scan sonar seafloor sediment images based on CBAM-BCEL1-INGAN is proposed, aiming to address the difficulties in acquiring and labeling datasets, as well as the insufficient diversity and quantity of data samples. Firstly, a Convolutional Block Attention Module (CBAM) is integrated into the residual blocks of the INGAN generator to enhance the learning of specific attributes and improve the quality of the generated images. Secondly, a BCEL1 loss function (combining binary cross-entropy and L1 loss functions) is introduced into the discriminator, enabling it to focus on both global image consistency and finer distinctions for better generation results. Finally, augmented samples are input into an AlexNet classifier to verify their authenticity. Experimental results demonstrate the excellent performance of the method in generating images of coarse sand, gravel, and bedrock, as evidenced by significant improvements in the Frechet Inception Distance (FID) and Inception Score (IS). The introduction of the CBAM and BCEL1 loss function notably enhances the quality and details of the generated images. Moreover, classification experiments using the AlexNet classifier show an increase in the recognition rate from 90.5% using only INGAN-generated images of bedrock to 97.3% using images augmented using our method, marking a 6.8% improvement. Additionally, the classification accuracy of bedrock-type matrices is improved by 5.2% when images enhanced using the method presented in this paper are added to the training set, which is 2.7% higher than that of the simple method amplification. This validates the effectiveness of our method in the task of generating seafloor sediment images, partially alleviating the scarcity of side-scan sonar seafloor sediment image data. [ABSTRACT FROM AUTHOR]