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Magnetic resonance imaging (MRI) was applied to determine the sex of polar cod (Boreogadus saida Lepechin, 1774) (Actinopterygii: Gadidae) and to follow the gonadal development in individual animals over time. Individual unanaesthetised fish were transferred to a measurement chamber inside a preclinical 9.4 T MRI scanner and continuously perfused with aerated seawater. A screening procedure at an average of 3.5 h, consisting of a set of MRI scans of different orientations, was repeated every 4 weeks on the same set of reproducing B. saida (n = 10) with a body length of about 20 cm. Adapted multi-slice flow-compensated fast low-angle shot (FcFLASH) and rapid acquisition with relaxation enhancement (RARE) protocols with an in-plane resolution of 313 µm and an acquisition time of 2.5 min were used to visualise the morphology of various organs, including the gonads within the field of view (FOV). The MR images provided high resolution, enabling specific sex determination, calculation of gonad volumes, and determination of oocyte sizes. Gonad maturation was followed over 4 months from November 2021 until shortly before spawning in February 2022. The gonad volume increased by 2.3-25.5% for males and by 11.5-760.7% for females during the observation period. From October to February, the oocyte diameter increased from 427 µm (n = 1) to 1346 ± 27 µm (n = 4). Interestingly, individual oocytes showed changes in MR contrast over time that can be attributed to the morphological development of the oocytes. The results fit well with previous literature data from classical invasive studies. The presented approach has great potential for various ecophysiological applications such as monitoring natural or delayed development of internal organs or sex determination under different environmental conditions.
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The polar cod, Boreogadus saida, is an abundant and ubiquitous forage fish and a crucial link in Arctic marine trophic dynamics. Our objective was to unravel layers of genomic structure in B. saida from Canadian waters, specifically screening for potential hybridization with the Arctic cod, Arctogadus glacialis, large chromosomal inversions, and sex-linked regions, prior to interpreting population structure. Our analysis of 53,384 SNPs in 522 individuals revealed hybridization and introgression between A. glacialis and B. saida. Subsequent population level analyses of B. saida using 12,305 SNPs in 511 individuals revealed three large (ca. 7.4-16.1 Mbp) chromosomal inversions, and a 2 Mbp region featuring sex-linked loci. We showcase population structuring across the Western and Eastern North American Arctic, and subarctic regions ranging from the Hudson Bay to the Canadian Atlantic maritime provinces. Genomic signal for the inferred population structure was highly aggregated into a handful of SNPs (13.8%), pointing to potentially important adaptive evolution across the Canadian range. Our study provides a high-resolution perspective on the genomic structure of B. saida, providing a foundation for work that could be expanded to the entire circumpolar range for the species.
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Polimorfismo de Nucleotídeo Único , Canadá , Animais , Regiões Árticas , Gadiformes/genética , Genética Populacional , Genômica/métodos , Genoma , Inversão Cromossômica/genética , Hibridização Genética , Masculino , FemininoRESUMO
There are a large number of simple landfills in hilly areas, and the results of previous studies have shown that pollutants in landfills can spread via interflow and cause surface source pollution. The hybrid activated sludge-membrane aerated bioreactor (H-MABR) developed in a previous study can be used for the treatment of interflow with a low chemical oxygen demand (COD)/total nitrogen (TN) ratio, and it has been shown to be effective in laboratory simulations. To investigate the effectiveness of the H-MABR in treating interflow around landfills in real-world applications, an in-situ pilot-scale evaluation of the effectiveness of H-MABR operation was conducted at a landfill. The results indicated that the removal efficiencies of COD, TN, and ammonia nitrogen in interflow by H-MABR were 87.1 ± 6.0%, 80.9 ± 7.9%, and 97.9 ± 1.4%, respectively. The removal rate of TN reached 148.6-205.6 g-N/m3·d. The concentration of each pollutant in the effluent was in accordance with China's "Standard for pollution control on the landfill site of municipal solid waste (GB16889-2008)," wherein the COD, TN, and ammonia nitrogen of effluent should be less than 100 mg/L, 40 mg/L, and 25 mg/L, respectively. The results of community composition analysis and PICRUSt analysis based on 16S rRNA gene sequencing showed that there were different dominant functional bacteria between the inner and outer rings, but functional genes involved in the nitrification-denitrification, assimilated nitrate reduction, and dissimilated nitrate reduction pathway were all detected. Furthermore, except for the nitrite oxidation gene narG, the abundance of which did not significantly differ between the inner and outer rings, the abundance of the other functional genes was higher in the outer ring than in the inner ring. An economic evaluation revealed that the operation cost of interflow treatment by the H-MABR was as low as ¥2.78/m3; thus, the H-MABR is a shock-load-resistant and cost-effective technology for interflow treatment.
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Biofilmes , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Desnitrificação , Nitrificação , Nitrogênio , Esgotos , Nitrogênio/metabolismo , Eliminação de Resíduos Líquidos/métodos , Projetos PilotoRESUMO
Brain PET imaging often faces challenges from head motion (HM), which can introduce artifacts and reduce image resolution, crucial in clinical settings for accurate treatment planning, diagnosis, and monitoring. United Imaging Healthcare has developed NeuroFocus, an HM correction (HMC) algorithm for the uMI Panorama PET/CT system, using a data-driven, statistics-based approach. The HMC algorithm automatically detects HM using a centroid-of-distribution technique, requiring no parameter adjustments. This study aimed to validate NeuroFocus and assess the prevalence of HM in clinical short-duration 18F-FDG scans. Methods: The study involved 317 patients undergoing brain PET scans, divided into 2 groups: 15 for HMC validation and 302 for evaluation. Validation involved patients undergoing 2 consecutive 3-min single-bed-position brain 18F-FDG scans-one with instructions to remain still and another with instructions to move substantially. The evaluation examined 302 clinical single-bed-position brain scans for patients with various neurologic diagnoses. Motion was categorized as small or large on the basis of a 5% SUV change in the frontal lobe after HMC. Percentage differences in SUVmean were reported across 11 brain regions. Results: The validation group displayed a large negative difference (-10.1%), with variation of 5.2% between no-HM and HM scans. After HMC, this difference decreased dramatically (-0.8%), with less variation (3.2%), indicating effective HMC application. In the evaluation group, 38 of 302 patients experienced large HM, showing a 10.9% ± 8.9% SUV increase after HMC, whereas most exhibited minimal uptake changes (0.1% ± 1.3%). The HMC algorithm not only enhanced the image resolution and contrast but also aided in disease identification and reduced the need for repeat scans, potentially optimizing clinical workflows. Conclusion: The study confirmed the effectiveness of NeuroFocus in managing HM in short clinical 18F-FDG studies on the uMI Panorama PET/CT system. It found that approximately 12% of scans required HMC, establishing HMC as a reliable tool for clinical brain 18F-FDG studies.
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Algoritmos , Encéfalo , Processamento de Imagem Assistida por Computador , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Adulto , Fluordesoxiglucose F18 , Artefatos , Cabeça/diagnóstico por imagem , Idoso de 80 Anos ou mais , Adulto JovemRESUMO
Traditional ultraviolet-visible spectroscopic quantitative analytical methods face challenges in simultaneous and long-term accurate measurement of chemical oxygen demand (COD) and nitrate due to spectral overlap and the interference from stochastic background caused by turbidity and chromaticity in water. Addressing these limitations, a compact dual optical path spectrum detection sensor is introduced, and a novel ultraviolet-visible spectroscopic quantitative analysis model based on physics-informed multi-task learning (PI-MTL) is designed. Incorporating a physics-informed block, the PI-MTL model integrates pre-existing physical knowledge for enhanced feature extraction specific to each task. A multi-task loss wrapper strategy is also employed, facilitating comprehensive loss evaluation and adaptation to stochastic backgrounds. This novel approach significantly outperforms conventional models in COD and nitrate measurement under stochastic background interference, achieving impressive prediction R2 values of 0.941 for COD and 0.9575 for nitrate, while reducing root mean squared error (RMSE) by 60.89 % for COD and 77.3 % for nitrate in comparison to the conventional chemometric model partial least squares regression (PLSR), and by 30.59 % and 65.96 %, respectively, in comparison to a benchmark convolutional neural network (CNN) model. The promising results emphasize its potential as a spectroscopic instrument designed for online multi-parameter water quality monitoring against stochastic background interference, enabling long-term accurate measurement of COD and nitrate levels.
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BACKGROUND: The Atlantic cod is a prolific species in the Atlantic, despite its inconsistent specific antibody response. It presents a peculiar case within vertebrate immunology due to its distinct immune system, characterized by the absence of MHCII antigen presentation pathway, required for T cell-dependent antibody responses. Thorough characterisation of immunoglobulin loci and analysis of the antibody repertoire is necessary to further our understanding of the Atlantic cod's immune response on a molecular level. RESULTS: A comprehensive search of the cod genome (gadmor3.0) identified the complete set of IgH genes organized into three sequential translocons on chromosome 2, while IgL genes were located on chromosomes 2 and 5. The Atlantic cod displayed a moderate germline V gene diversity, comprising four V gene families for both IgH and IgL, each with distinct chromosomal locations and organizational structures. 5'RACE sequencing revealed a diverse range of heavy chain CDR3 sequences and relatively limited CDR3 diversity in light chains. The analysis highlighted a differential impact of V-gene germline CDR3 length on receptor CDR3 length between heavy and light chains, underlining different recombination processes. CONCLUSIONS: This study reveals that the Atlantic cod, despite its inconsistent antibody response, maintains a level of immunoglobulin diversity comparable to other fish species. The findings suggest that the extensive recent duplications of kappa light chain genes do not result in increased repertoire diversity. This research provides a comprehensive view of the Atlantic cod's immunoglobulin gene organization and repertoire, necessary for future studies of antibody responses at the molecular level.
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Gadus morhua , Sequenciamento de Nucleotídeos em Larga Escala , Animais , Gadus morhua/genética , Cadeias Pesadas de Imunoglobulinas/genética , Imunoglobulinas/genética , Loci Gênicos , Genes de Imunoglobulinas , Região Variável de Imunoglobulina/genéticaRESUMO
Municipal wastewater treatment systems use the chemical oxygen demand test (COD) to identify organic contaminants in industrial effluents that impede treatment due to their high concentration. This study reduced the COD levels in tannery wastewater using a multistage treatment process that included Fenton oxidation, chemical coagulation, and nanotechnology based on a synthetic soluble COD standard solution. At an acidic pH of 5, Fenton oxidation reduces the COD concentration by approximately 79%. It achieves this by combining 10 mL/L of H2O2 and 0.1 g/L of FeCl2. Furthermore, the author selected the FeCl3 coagulant for the coagulation process based on the best results of comparisons between different coagulants. At pH 8.5, the coagulation dose of 0.15 g/L achieved the maximum COD removal efficiency of approximately 56.7%. Finally, nano bimetallic Fe/Cu was used to complete the degradation and adsorption of the remaining organic pollutants. The XRD, SEM, and EDX analyses proved the formation of Fe/Cu nanoparticles. A dose of 0.09 g/L Fe/Cu NPs, 30 min of contact time, and a stirring rate of 200 rpm achieve a maximum removal efficiency of about 93% of COD at pH 7.5. The kinetics studies were analyzed using pseudo-first-order P.F.O., pseudo-second-order P.S.O., and intraparticle diffusion models. The P.S.O. showed the best fit among the kinetic models, with an R2 of 0.998. Finally, the authors recommended that technique for highly contaminated industrial effluents treatment for agriculture or industrial purposes.
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Basking sharks (Cetorhinus maximus) seasonally aggregate in coastal surface waters of the North Atlantic, providing opportunities for visual observation. While putative courtship displays have been observed, actual copulation has not been documented. Here we examine video collected by an unmanned aerial vehicle ("drone") of novel behavioral interactions between basking sharks in Cape Cod Bay, Massachusetts in May 2021. The behaviors, including close following and tight concentric circling, are consistent with pre-copulatory behavior observed in other shark species. These observations provide new insights into the pre-copulatory behavior of basking sharks.
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Egg quality in fishes is commonly determined by fertilisation success and cleavage patterns as a phenotypic outcome of underlying regulatory mechanisms. Although these phenotypic estimators of egg quality are useful in farming conditions, these "good quality" egg batches do not always translate to good larval growth and survival. The identification of genes involved in embryonic development may help find links between genetic factors of maternal origin and egg quality. Herein, the relative expression of seven stage-specific developmental genes of Atlantic cod was analysed using quantitative PCR to understand the function during embryogenesis and its relationship with egg quality. Genes ccnb2 and pvalb1 showed significant differential expression between developmental stages and significant upregulation from blastula and somite stages, respectively. The comparison of spawning batches showed that the relative gene expression of genes ccnb2, acta, tnnt3 and pvalb1 was significantly higher from the middle of the spawning season where phenotypic quality estimators establish the best egg quality. Moreover, a positive significant correlation was observed between quality estimators based on egg morphology and the genetic expression of genes acta and acta1 during somitogenesis. This study suggests that the combination of quality estimators, genetics and batch timing could help optimise reproductive protocols for commercial stocks of Atlantic cod.
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Gadus morhua , Regulação da Expressão Gênica no Desenvolvimento , Óvulo , Fenótipo , Animais , Gadus morhua/genética , Gadus morhua/crescimento & desenvolvimento , Óvulo/metabolismo , Óvulo/crescimento & desenvolvimento , Estações do Ano , Feminino , Reprodução/genética , Desenvolvimento Embrionário/genéticaRESUMO
This study aimed to assess the effect of novel thermal glycation, utilizing microwave processing (100-150 °C) combined with sugars (glucose and lactose), on the in vitro protein digestibility, peptides, secondary structures, microstructures, and allergenic properties of Atlantic cod. The research demonstrated that microwave heating at 150 °C with glucose significantly reduced cod allergenicity by up to 16.16%, while also enhancing in vitro protein digestibility to 69.05%. Glucose was found to be more effective than lactose in conjunction with microwave heating in reducing the allergenicity of Atlantic cod. Moreover, treatments conducted at 150 °C were more effective in increasing in vitro protein digestibility and peptide content compared to those at 100 °C. This study revealed that the novel processing technique of thermal glycation effectively reduced the allergenicity of Atlantic cod. It also offered fresh insights into the potential benefits of combining microwave heating with sugars.
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This study explores the optimization of iron electrocoagulation for treating laundry greywater, which accounts for up to 38% of domestic greywater. Characterized by high concentrations of surfactants, detergents, and suspended solids, laundry greywater presents complex challenges for treatment processes, posing significant environmental and health risks. Utilizing response surface methodology (RSM), this research developed a second-order polynomial regression model focused on key operational parameters such as the area-to-volume ratio (A/V), current density, electrolysis time, and settling time. Optimal treatment conditions were identified: an A/V ratio of 30 m2/m3, a current density of 10 mA/cm2, an electrolysis duration of 50 min, and a settlement period of 12 h. Under these conditions, exceptional treatment outcomes were achieved, with turbidity removal reaching 94.26% and COD removal at 99.64%. The model exhibited high effectiveness for turbidity removal, with an R2 value of 94.16%, and moderate effectiveness for COD removal, with an R2 value of 75.90%. The interaction between the A/V ratio and electrolysis time particularly underscored their critical role in electrocoagulation system design. Moreover, these results highlight the potential for optimizing electrocoagulation parameters to adapt to daily fluctuations in greywater production and meet specific household reuse needs, such as toilet flushing. This tailored approach aims to maximize contaminant separation and coagulant efficiency, balance energy use and operational costs, and contribute to sustainable water management.
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Recent escalating concerns surrounding textile wastewater pollution and the urgent need for sustainable treatment solutions to mitigate its environmental impact. This study investigates the multifaceted effects of Spirulina platensis (SP) cultivation in textile wastewater from two different sources (TWW1 and TWW2), focusing on growth kinetics, Chemical Oxygen Demand (COD), and nutrient removal percentage, and seed germination enhancement. Results showed that SP exhibited comparable growth performance in TWW1 and TWW2 to the control, indicating its potential for sustainable wastewater treatment. Moreover, maximum COD removal percentages were achieved, reaching 62.59 ± 1.88 % for TWW1 and 46.68 ± 1.40 % for TWW2 on day 5. The COD removal process aligns best with the first-order kinetic model. Nutrient removal rates showed decreasing trends over time, with maximum phosphate removal percentages of 36.42 ± 0.73 % for TWW1 and 62.18 ± 1.24 % for TWW2, and maximum ammonia removal percentages of 59.34 ± 1.18 % for TWW1 and 69.31 ± 1.39 % for TWW2. FTIR analysis confirmed pollutant removal-induced changes in algal biomass functional groups. Seed germination studies indicated enhanced shoot and root development of vigna radiatas using treated TWW1 and TWW2 compared to the control, suggesting potential applications for irrigation. An increase in the lipid & carbohydrate content post-treatment was observed and it would be suitable for biofuel production. This comprehensive assessment demonstrates the synergistic benefits of phycoremediation in simultaneously removing pollutants, promoting plant growth, and enhancing wastewater treatment efficiency, underscoring its potential for sustainable water management practices.
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Germinação , Sementes , Spirulina , Eliminação de Resíduos Líquidos , Águas Residuárias , Spirulina/crescimento & desenvolvimento , Spirulina/metabolismo , Águas Residuárias/química , Sementes/crescimento & desenvolvimento , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Têxteis , Nutrientes/metabolismo , Vigna/crescimento & desenvolvimento , Vigna/metabolismoRESUMO
Oil refineries produce annually large quantities of oily sludge and non-biodegradable wastewater during petroleum refining that require adequate management to minimize its environmental impact. The fraction solid of the oily sludge accounts for 25 wt% and without treatment for their valorization. This work is focused on the valorization of these solid particles through their transformation into porous materials with enhanced properties and with potential application in the catalytic wet air oxidation (CWAO) of a non-biodegradable spent caustic refinery wastewater. Hence, dealing with the valorization and treatment of both refinery wastes in a circular approach aligned with the petrol refinery transformations by 2050. The obtained oily sludge carbonaceous materials showed improved surface area (260-762 m2/g) and a high Fe content. The good catalytic performance of these materials in CWAO processes has been attributed to the simultaneous presence of surface basic sites and iron species. Those materials with higher content of Fe and basic sites yielded the highest degradation of organic compounds present in the spent caustic refinery wastewater. In particular, the best-performing material ACT-NP 1.1 (non-preoxidated and thermically treated with 1:1 mass ratio KOH:solid) showed a chemical oxygen demand (COD) removal of 60 % after 3 h of reaction and with a higher degradation rate than that achieved with thermal oxidation without catalyst (WAO) and that using an iron-free commercial activated carbon. Moreover, the biodegradability of the treated wastewater increased up to 80% (from ca. 31% initially of the untreated effluent). Finally, this material was reused up to three catalytic cycles without losing metal species and keeping the catalytic performance.
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Oxirredução , Esgotos , Águas Residuárias , Catálise , Esgotos/química , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Petróleo , Análise da Demanda Biológica de OxigênioRESUMO
The presence of a large amount of organic and inorganic pollutants in dairy effluent is a substantial environmental issue. This study investigated electrocoagulation (EC) as a potential treatment method for dairy wastewater under different operating conditions, such as applied voltage (5-25 V), electrolysis time (30-90 min), and inter-electrode distance (1-2 cm) by using aluminum electrodes. This study focuses on achieving the maximum removal of BOD, COD, and nitrate in dairy effluents with the aforementioned operating conditions. The process was optimized using the response surface methodology (RSM) and Taguchi method. RSM method optimized the electrocoagulation operating conditions such as the voltage at 23.75 V, time of 90 min, and inter-electrode distance at 1.07 cm. This optimization achieved the maximum removal percentage of BOD, COD, and nitrate at 79.06%, 84.35%, and 79.64%, respectively, in dairy effluent. Taguchi method optimized the electrocoagulation parameters such as the voltage at 25 V, time duration of 90 min, and inter-electrode distance of 1.00 cm, showcasing improved removal percentages of BOD, COD, and nitrate as 90.54%, 89.28%, and 82.74% respectively. The current study attempts to understand the optimization efficiencies between Taguchi method and response surface method for diary wastewater treatment.
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Indústria de Laticínios , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Indústria de Laticínios/métodos , Poluentes Químicos da Água/análise , Eletrocoagulação/métodos , Nitratos/análise , Análise da Demanda Biológica de OxigênioRESUMO
A bioelectrochemical upflow anaerobic sludge blanket (BE-UASB) was constructed and compared with the traditional UASB to investigate the role of bioelectrocatalysis in modulating methanogenesis and sulfidogensis involved within anaerobic treatment of high-sulfate methanolic wastewater (COD/SO42- ratio ≤ 2). Methane production rate for BE-UASB was 1.4 times higher than that of the single UASB, while SO42- removal stabilized at 16.7%. Bioelectrocatalysis selectively enriched key functional anaerobes and stimulated the secretion of extracellular polymeric substances, especially humic acids favoring electron transfer, thereby accelerating the electroactive biofilms development of electrodes. Methanomethylovorans was the dominant genus (35%) to directly convert methanol to CH4. Methanobacterium as CO2 electroreduction methane-producing archaea appeared only on electrodes. Acetobacterium exhibited anode-dependence, which provided acetate for sulfate-reducing bacteria (norank Syntrophobacteraceae and Desulfomicrobium) through synergistic coexistence. This study confirmed that BE-UASB regulated the microbial ecology to achieve efficient removal and energy recovery of high-sulfate methanolic wastewater.
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Metano , Metanol , Esgotos , Sulfatos , Águas Residuárias , Águas Residuárias/microbiologia , Metanol/metabolismo , Metano/metabolismo , Sulfatos/metabolismo , Esgotos/microbiologia , Anaerobiose , Reatores Biológicos/microbiologia , EletrodosRESUMO
The present work deals with the optimization of basic fuchsin dye removal from an aqueous solution using the ultraviolet UV/H2O2 process. Response Surface Modeling (RSM) based on Box-Behnken experimental design (BBD) was applied as a tool for the optimization of operating conditions such as initial dye concentration (10-50 ppm), hydrogen peroxide dosage (H2O2) (10-20 mM/L) and irradiation time (60-180 min), at pH = 7.4 under ultra-violet irradiation (254 nm and 25 W intensity). Chemical oxygen demand (COD abatement) was used as a response variable. The Box-Behnken Design can be employed to develop a mathematical model for predicting UV/H2O2 performance for COD abatement. COD abatement is sensitive to the concentration of hydrogen peroxide and irradiation time. Statistical analyses indicate a high correlation between observed and predicted values (R2 > 0.98). In the BBD predictions, the optimal conditions in the UV/H2O2 process for removing 99.3% of COD were found to be low levels of pollutant concentration (10 ppm), a high concentration of hydrogen peroxide dosage (20 mM/L), and an irradiation time of 80 min.
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Peróxido de Hidrogênio , Raios Ultravioleta , Poluentes Químicos da Água , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Corantes/química , Modelos Químicos , Eliminação de Resíduos Líquidos/métodos , Modelos TeóricosRESUMO
Polar cod (Boreogadus saida) is an endemic key species of the Arctic Ocean ecosystem. The ecology of this forage fish is well studied in Arctic shelf habitats where a large part of its population lives. However, knowledge about its ecology in the central Arctic Ocean (CAO), including its use of the sea-ice habitat, is hitherto very limited. To increase this knowledge, samples were collected at the under-ice surface during several expeditions to the CAO between 2012 and 2020, including the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. The diet of immature B. saida and the taxonomic composition of their potential prey were analysed, showing that both sympagic and pelagic species were important prey items. Stomach contents included expected prey such as copepods and amphipods. Surprisingly, more rarely observed prey such as appendicularians, chaetognaths, and euphausiids were also found to be important. Comparisons of the fish stomach contents with prey distribution data suggests opportunistic feeding. However, relative prey density and catchability are important factors that determine which type of prey is ingested. Prey that ensures limited energy expenditure on hunting and feeding is often found in the stomach contents even though it is not the dominant species present in the environment. To investigate the importance of prey quality and quantity for the growth of B. saida in this area, we measured energy content of dominant prey species and used a bioenergetic model to quantify the effect of variations in diet on growth rate potential. The modeling results suggest that diet variability was largely explained by stomach fullness and, to a lesser degree, the energetic content of the prey. Our results suggest that under climate change, immature B. saida may be at least equally sensitive to a loss in the number of efficiently hunted prey than to a reduction in the prey's energy content. Consequences for the growth and survival of B. saida will not depend on prey presence alone, but also on prey catchability, digestibility, and energy content.
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The aim of this work is the description and characterization of a severe microsporidian infection in a batch of salted and dried cod. Particularly, the case involves a batch of approximately 800 kg obtained from Gadus macrocephalus (Food and Agriculture Organization Zone 61 - Northwest Pacific Ocean), which, after rehydration and sectioning operations, underwent routine company checks before packaging. In about 20% of the samples, the presence of whitish nodules with a diameter ranging from 1 to 2 mm was observed on the surface of the fillets and in cross-section. The lesions ranged from a few units to 10 per cm2. Some samples were subjected to fresh microscopic observation with the stereomicroscope, confirming the nodular nature of the lesions, which were often confluent, alternating with empty spaces, giving the tissue a honeycombing aspect. The histological examination at low magnification allowed us to observe the heavy vacuolization of nodular lesions irregularly surrounded by a spongy-like wall. The observation at higher magnification of other sections allowed us to identify intra-myofibrillar cists containing presumptive microsporidian elements. The tissue damage derived from the technological processes and gravity of lesions did not allow a morphological characterization of presumptive protozoans. The molecular examination of the nodular lesions and the analysis of the sequence of an 897 bp fragment of the small subunit 16S rRNA revealed 100% identity with Microsporidium theragrae (GenBank accession number MT928885-89) first isolated from the skeletal muscles of Gadus chalcogrammus specimens from the Sea of Okhotsk. This finding confirms the importance of selecting suppliers and raw materials in the seafood industry, as well as the usefulness of an effective traceability system.
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This study aims to improve COD, NH3-N, and turbidity removal from Bingöl's leachate using a single-reactor integrated electrocoagulation (EC)-coal-based powdered activated carbon (CBPAC) process under various experimental conditions. In the EC-CBPAC process, three stainless-steel cathodes and three aluminum electrodes were connected to the negative and positive terminals of the power supply, respectively. The initial concentrations in the leachate were 1044 mg O2/L for COD, 204 mg/L for NH3-N, and 57 NTU (or 71.25-mg (NH2)2H2SO4/L) for turbidity, respectively. After a 40-min EC-CBPAC process, with a CBPAC dosage of 5 g/L and pH of 5 for COD and turbidity, and 9.5 for NH3-N, the optimum removal efficiencies for COD, NH3-N, and turbidity were achieved at 92%, 40%, and 91%, respectively. When the EC process was applied without CBPAC under the same experimental conditions, the removal efficiencies of COD, NH3-N, and turbidity were 87%, 28%, and 54%, respectively. Before and after the EC-CBPAC process, the Brunauer-Emmett-Teller (BET) surface area, pore volume, and mean pore diameter of the CBPAC were found to be (888 m2/g, 0.498 cm3/g, and 22.28 Å) and (173 m2/g, 0.18 cm3/g, and 42.8 Å), respectively. The optimum pseudo-first-order (PFO) rate constants for COD, turbidity, and NH3-N were determined to be 3.15 × 10-2, 4.77 × 10-2, and 8.8 × 10-3 min-1, respectively. With the current density increasing from 15 to 25 mA/cm2, energy consumption, unit energy consumption, and total cost increased from 68.7 to 122.4 kWh/m3, 6.948 to 15.226 kWh/kg COD, and 0.85 to 1.838 $/kg COD, respectively. PRACTITIONER POINTS: EC-CBPAC process has greater COD, NH3-N, and turbidity removal efficiency than EC process. COD and turbidity achieved their optimum disposal efficiencies at 92% and 91%, respectively, at pH 5 The most efficient disposal efficiency for NH3-N was observed to be 40% at pH 9.5. EC-CBPAC process increased removal efficiencies for COD, NH3-N, and turbidity by 20%, 19%, and 38%, respectively, compared with EC alone. The turbidity, NH3-N, and COD disposal fitted PSO model due to high correlation values (R2 0.94-0.99).
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Carvão Vegetal , Poluentes Químicos da Água , Carvão Vegetal/química , Poluentes Químicos da Água/química , Cinética , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodosRESUMO
It is very important to choose a suitable method and catalyst to treat coking wastewater. In this study, Fe-Ce-Al/MMT catalysts with different Fe/Ce molar ratios were prepared, characterized by XRD, SEM, and N2 adsorption/desorption, and treated with coking wastewater. The results showed that the optimal Fe-Ce-Al/MMT catalyst with a molar ratio of Fe/Ce of 7/3 has larger interlayer spacing, specific surface area, and pore volume. Based on the composition analysis of real coking wastewater and the study of phenol simulated wastewater, the response surface test of the best catalyst for real coking wastewater was carried out, and the results are as follows: initial pH 3.46, H2O2 dosage 19.02 mL/L, Fe2+ dosage 5475.39 mL/L, reaction temperature 60 °C, and reaction time 248.14 min. Under these conditions, the COD removal rate was 86.23%.