Search

Up to now, only limited data are available on the influence of process-related variables [influent characteristics, solids retention time (SRT), hydraulic retention time (HRT), biomass recirculation rates, process configuration, biochemical reaction rates, etc.] on oxygen transfer, as stated in the aeration manuals. Recently, standards have been updated in regard to oxygen transfer testing in clean water as well as in in-process wastewater. Unfortunately, the situation has not improved since the publication of these documents. In particular, little information exists on alpha (α) and oxygen transfer efficiency (OTE)f in biological nutrient removal (BNR) processes to study the impact of biochemical reactions on oxygen transfer under controlled process conditions. A new model is herewith proposed that would deal with the effect of oxygen consumption rate due to these substrate materials. [ABSTRACT FROM AUTHOR]

Addressing critical environmental challenges such as greenhouse gas emissions, global warming, and eutrophication demands urgent and innovative solutions. In recent years, microalgae have emerged as a promising avenue for addressing these pressing issues. In this study, the combination of dairy and municipal wastewater is proposed as a culture medium for cultivating microalgae strains capable of sequestering atmospheric CO2. Specifically, the growth of Chlorella vulgaris was investigated using Bold's basal medium, along with varying concentrations of municipal and dairy wastewater, both with and without CO2 supplementation, to assess their CO2 capture potential. Concurrently, the efficiency of chemical oxygen demand (COD), total nitrogen, potassium, and phosphate removal from the wastewater was evaluated. Additionally, the combination of wastewater media with CO2 supplementation yielded the highest CO2 uptake rates, indicating the feasibility of simultaneous CO2 capture during microalgae cultivation. Media composition with 25% municipal wastewater: 75% dairy wastewater supplemented with CO2 demonstrated superior COD elimination with a higher percentage of nutrient removal from wastewater compared to other wastewater proportions. The nutrient removal capacity of aforementioned media also comes in line with high CO2 sequestration rate (13.57 mg L−1 h−1). These findings underscore the potential of utilizing wastewater from diverse sources as a viable culture medium for microalgae cultivation, facilitating concurrent CO2 capture and wastewater treatment. [ABSTRACT FROM AUTHOR]

The management of landfill leachate presents a significant environmental challenge, necessitating a comprehensive and dynamic treatment approach. This comprehensive review delves into the critical issue of landfill leachate treatment, exploring its environmental impact, treatment technologies, regulatory frameworks, and the path towards sustainable management practices. This review explores the complexities of landfill leachate, emphasizing the need for sustainable waste management practices to safeguard environmental health. Our analysis highlights the evolution of conventional and advanced treatment technologies designed to mitigate these risks, focusing on membrane technologies, advanced oxidation processes, and the promising potential of emerging techniques such as adsorption and biological nutrient removal. These technologies are evaluated for their efficiency, cost implications, and sustainability impacts, underscoring the challenges and opportunities within the current landscape of leachate treatment. The review aims to provide insights into designing efficient and effective treatment systems through a detailed analysis of conventional and advanced treatment methods. By examining a case study in Changsha City, the effectiveness of a comprehensive treatment system integrating various technologies is demonstrated. The review underscores the interconnectedness of human activities, environmental health, and waste management, emphasizing the importance of a holistic approach. It stresses the continuous improvement of leachate treatment technologies and the adoption of sustainable practices to reduce the environmental footprint of landfills. Ultimately, it calls for integrating multiple treatment processes, economic considerations, and readiness to address future challenges in landfill leachate treatment, contributing to the advancement of sustainable waste management practices. [ABSTRACT FROM AUTHOR]

Aerobic granular sludge (AGS) is an emerging replacement for activated sludge for advanced and sustainable wastewater treatment. This study examined the beneficial effect of granular activated carbon (GAC) addition on AGS formation and sewage treatment in tropical climates. GAC shortened the start-up period for granulation by minimizing sludge washout. Ammonium was removed effectively through partial nitrification and denitritation. Enhanced biological phosphate removal was established with ~98% removal efficiencies. Improved granulation, enrichment of polyphosphateaccumulating organisms, and establishment of enhanced biological phosphate removal pathways in tropical climates recommend GAC addition as a simple and potential start-up strategy for AGS-based biological wastewater treatment. [ABSTRACT FROM AUTHOR]

Biological nitrogen removal is the main method of nitrogen pollution removal in sewage treatment plants. It has the advantages of low carbon and low cost. For the low carbon nitrogen ratio wastewater represented by municipal sewage, how to strengthen the denitrification functional flora and stabilize the biological nitrogen removal efficiency remains to be studied. In this study, two kinds of biochar carriers with enhanced nitrogen removal function were prepared by acid and alkali modification. And the enhanced denitrification nitrogen removal process was established. The research results showed that the total nitrogen removal rate of the system after adding biochar was increased by 7.29%~29.51% compared with the system with? out adding biochar. The nitrogen removal efficiency of acid and alkali modified biochar was improved by 19.37% and 29.55%, respectively, compared with that of the unmodified biochar system. The maximum nitrogen removal rate of alkali modified biochar system was 59.76%. In terms of electron transfer activity and nitrite reductase activity, the alkali-modified biochar enhanced system increased by 91.8% and 47.1%, respectively, compared with the non-added biochar system. At the same time, the high-throughput sequencing results showed that 67.3% of the bacteria involved in denitrification in the alkali-modi? fied biochar system. Bacillus and Thauera with denitrification were the dominant strains in the alkali-modified biochar system. The alkali-modified biochar promoted the growth of denitrifying bacteria more than the acid-modified biochar. Therefore, the target regulation of denitrification and nitrogen removal ability was established. [ABSTRACT FROM AUTHOR]

Phosphorus (P) discharge from anthropogenic sources, notably sewage effluent and agricultural runoff, significantly contributes to eutrophication in aquatic environments. Stringent regulations have heightened the need for effective P removal technologies in wastewater treatment processes. This paper provides a comprehensive review of current P removal methods, focusing on both biological and chemical approaches. Biological treatments discussed include enhanced biological P removal in activated sludge systems, biological trickling filters, biofilm reactors, and constructed wetlands. The efficiency of microbial absorption and novel biotechnological integrations, such as the use of microalgae and fungi, are also examined. Chemical treatments reviewed encompass the application of metal salts, advanced oxidation processes such as chlorination, ozonation, and the Fenton reaction, as well as emerging techniques including the Electro-Fenton process and photocatalysis. Analytical methods for P, including spectrophotometric techniques and fractionation analyses, are evaluated to understand the dynamics of P in wastewater. This review critically assesses the strengths and limitations of each method, aiming to identify the most effective and sustainable solutions for P management in wastewater treatment. The integration of innovative strategies and advanced technologies is emphasized as crucial for optimizing P removal and ensuring compliance with environmental regulations. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) 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.)

• Increasing periodic aeration rate reduced irreversible fouling of GDM. • Reclaimed wastewater was feasible for hydroponic vegetable cultivations. • Plants grown with treated water were comparable to those with fertilizer. • Shifting nutrient level and operation mode influenced plant growth profile. • Basil grown in reclaimed water had less health risk impact compared to lettuce. In this study, a gravity-driven membrane (GDM) filtration system and hydroponic system (cultivating basil and lettuce) were combined for nutrient recovery from primary municipal wastewater. The GDM system was optimized by increasing the periodic air sparging flow rate from 1 to 2 L/min (∼15 hr per 3–4 days), resulting in a ∼52% reduction of irreversible fouling. However, the total fouling was not alleviated, and the water productivity remained comparable. The GDM-filtrated water was then delivered to hydroponic systems, and the effects of hydroponic operation conditions on plant growth and heavy metal uptake were evaluated, with fertilizer- and tap water-based hydroponic systems and soil cultivation system (with tap water) for comparison. It was found that (i) the hydroponic system under batch mode facilitated to promote vegetable growth with higher nutrient uptake rates compared to that under flow-through feed mode; (ii) a shift in nutrient levels in the hydroponic system could impact plant growth (such as plant height and leaf length), especially in the early stages. Nevertheless, the plants cultivated with the GDM-treated water had comparable growth profiles to those with commercial fertilizer or in soils. Furthermore, the targeted hazard quotient levels of all heavy metals for the plants in the hydroponic system with the treated water were greatly lower than those with the commercial fertilizer. Especially, compared to the lettuce, the basil had a lower heavy metal uptake capability and displayed a negligible impact on long-term human health risk, when the treated water was employed for the hydroponic system. [Display omitted] [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Community domestic wastewater contains organic substances that can be decomposed through natural processes. Treatment using oxidation pond systems is popular in tropical zones because these locations provide a climate suitable for the growth and organic decomposition activities of various bacteria that remove organic contaminants from wastewater. Given that bacteria play an important role in the biodegradation of organic substances in wastewater treatment plants, their degradation activity is used as an indicator of water quality. The purpose of this study is to examine the vertical variability of bacteria in natural treatment oxidation ponds in tropical zones.METHODS: Wastewater samples were collected from an oxidation pond at 3 different depths (0–0.6, 0.6–1.5 and more than 1.5 meter), and their chemical, physical and biological qualities were analysed. Next-generation sequencing techniques were used to identify bacterial diversity, and the water quality at each depth was applied as an indicator of bacterial degradation activities.FINDINGS: Community domestic wastewater contained 10 major bacterial phyla that differed at different depths. Amongst these phyla, the Actinobacteriota dominated (25.35 to 28.23 percent), followed by Cyanobacteria (19.49 to 21.57percent), Planctomycetota (15.50 to 17.41 percent), Firmicutes (9.97 to 10.79 percent), Proteobacteria (9.73 to 10.79 percent), Verrucomicrobiota (6.47 to 7.69 percent), Chloroflexi (2.79 to 2.99 percent), Bacteriota (0.96 to 1.41 percent), Acidobacteriota (0.70 to 0.80 percent) and SAR324 clade (marine group B) (0.69 to 0.61 percent). Four organic substances were found in contaminated domestic wastewater. 1) Photosynthetic cyanobacteria and phytoplankton performed aerobic degradation and accounted for the dissolved oxygen levels of 7.76, 7.45 and 7.42 milligrams per liter, respectively at various depths along the vertical profile. 2) Bacteria and archaeans that participate in carbon compound treatment included Planctomycetes, Verrucomicrobiota, Bacteroidota and Euryarcheota. These bacteria exhibited a treatment efficiency for biochemical oxygen demand and low abundance at all depths. Biological oxygen demand increased to 23.11, 24.27 and 34.48 milligrams per liter with depth. 3) Nitrogen-cycling bacteria included nitrifying and denitrifying bacteria. They belonged to the Actinobacteriota, Planctomycetota, Firmicutes, Verrucomicrobiota, Chloroflexi, Bacteriota, Protrobacteria and Acidobacteriota phyla. They exhibited an ammonia-nitrogen treatment efficiency of 91.73 percent. 4) Phosphorus cycling–related bacteria in the Actinobacteriota phylum presented the orthophosphorus treatment efficiency of 65.41 percent.CONCLUSION: The results of this study suggested that bacterial communities did not significantly differ along oxidation depth because they work together with chemotrophs, which participate in organic substance decomposition, and phototrophs, which are involved in oxygen generation and nutrient removal. All of the bacteria found in domestic wastewater benefit and support oxidation pond systems in tropical zones. Anaerobic bacteria can be found in wastewater and used in treatment systems due to their protective mechanisms against oxygen toxicity and self-repair mechanisms. The knowledge gained from this study can be used as a reference in future works on natural wastewater treatment systems.

Background: The microbiota in wastewater treatment plants (WWTPs) and incoming wastewater is critical for the treatment process, the preservation of natural ecosystems and human health, and for the recovery of resources and achievement of sustainability goals. Both core species and conditionally rare and abundant taxa (CRAT) are considered process-critical but little is known about identity as well as true functional and ecological importance. Here, we present a comprehensive investigation of the microbiota of 84 municipal activated sludge (AS) plants with nutrient removal treating ~ 70% of all wastewater within a confined geographical area, Denmark (43,000 km2). With the use of an ecosystem-specific database (MiDAS 5.2), species-level classification allowed us to investigate the core and CRAT species, whether they were active, and important factors determining their presence. Results: We established a comprehensive catalog of species with names or placeholder names showing each plant contained approx. 2,500 different species. Core and CRAT represented in total 258 species, constituting around 50% of all reads in every plant. However, not all core and CRAT could be regarded as process-critical as growth rate calculations revealed that 43% did not grow in the AS plants and were present only because of continuous immigration from the influent. Analyses of regional microbiota differences and distance decay patterns revealed a stronger effect for species than genera, demonstrating that geography had a clear effect on the AS microbiota, even across a limited geographical area such as Denmark (43,000 km2). Conclusions: The study is the first comprehensive investigation of WWTPs in a confined geographical area providing new insights in our understanding of activated sludge microbiology by introducing a concept of combining immigration and growth calculation with identifying core and CRAT to reveal the true ecosystem-critical organisms. Additionally, the clear biogeographical pattern on this scale highlights the need for more region-level studies to find regional process-critical taxa (core and CRAT), especially at species and amplicon sequence variant (ASV) level. [ABSTRACT FROM AUTHOR]

The article focuses on the application of green microbiology to promote sustainability in water management, agriculture, and energy production. Topics include microbial pollutant degradation in water, the use of microbes as biofertilizers and biostimulants in agriculture, and advancements in microbial fuel cells for energy generation.

Background: The soil-borne fungi, Rhizoctonia solani and Sclerotium rolfsii, are major pathogens of Brassicae crops. This study was performed to clarify the relationship between the accumulation pattern of the genus Trichoderma and disease suppression in frequently inoculated soils with binucleate Rhizoctonia (BNR), Rhizoctonia solani and Sclerotium rolfsii. Results: As compared to the control group, five Trichoderma virens strains isolated from soil inoculated with R. solani or BNR significantly reduced the severity of S. rolfsii (85.6–100% covering percentage) and R. solani (95.7–100% covering percentage). Similarly, five T. hamatum strains obtained from soil inoculated with R. solani were shown to be highly suppressive against S. rolfsii (83.9–97.1% covering percentages) and R. solani (60.2–96.2% covering percentages). Four out of five T. hamatum strains obtained from soil infected with S. rolfsii exhibited considerable suppression against S. rolfsii (63.7–91.2% covering percentages), while the SM5 strain did not. The phylogenetic analysis of the TEF and ITS regions of Trichoderma hamatum revealed that most isolates were classified into the same cluster with homology of 99–100%. Five strains of each T. virens and T. hamatum were isolated from the suppressive soil with high antagonistic potentials against R. solani and S. rolfsii. Suppression and antagonistic activity of T. hamatum isolated from soil frequently inoculated with sterile barley grains were negligible, whereas T. hamatum isolated from frequently inoculated soil with BNR and R. solani demonstrated considerable suppression of the pathogens and antagonistic activity. Accumulation and quantification of T. virens and T. hamatum were confirmed using loop-mediated isothermal amplification (LAMP). Conclusion: In conclusion, disease suppression in frequently inoculated soil with BNR, R. solani and S. rolfsii was due to Trichoderma spp. accumulated selectively in each replicate of soil inoculation. [ABSTRACT FROM AUTHOR]

Constructed wetlands (CWs) are a widely used technology for the treatment of wastewater, with Free Water Surface Constructed Wetlands (FWS CWs) being the simplest configuration. However, there is currently no consensus on the Hydraulic Retention Time (HRT) that optimizes P removal efficiency. To address this issue, this study conducted a bibliometric review of 85 scientific articles published between 1997 and 2021 that investigated the relationship between P removal and the HRT in FWS CWs. Scientometric maps were constructed to identify key topics, and bibliometric surveys were used to refine and explore the relationship between P removal and HRT. The analysis found a high correlation between P removal and HRT across all scales of the FWS CW systems, ranging from moderate to very strong. Specifically, the regressions between P removal efficiency and HRT were 73%, 70%, and 67% for lab-scale, pilot-scale, and real-scale systems, respectively. Overall, the FWS CWs demonstrated strong P removal efficiency, with removal rates reaching 95%, making them a promising technology for the tertiary treatment of effluents with a focus on nutrient removal and recovery. Future studies that focus on the many parameters of CW, especially on how macrophytes management affects the nutrient removal performance of these systems, are necessary to enrich our knowledge of CWs and optimize the application of this technology to wastewater treatment. [ABSTRACT FROM AUTHOR]

Moving bed bioreactors are efficient for the removal of nitrogen effluents by simultaneous nitrification and denitrification (SND), which is particularly challenging for effluents with low C/N ratio due to insufficient carbon available for denitrification. The addition of external organic carbon in such cases increases treatment costs. Endogenous degradation of biomass offers a cost-effective and persistent source of carbon. Internal carbon leads to low denitrification rates and optimizing the biomass content leads to a sustainable solution for treating such effluents. The present study aims to optimize the process of SND using endogenous carbon by investigating the effect of operational parameters like dissolved oxygen, influent ammonium (NH4–N) loading, hydraulic retention time (HRT) and carrier filling ratio (CFR). The synthetic wastewater used in the study does not inherently contain any organic carbon, thus indicating the responsible carbon for denitrification to be of internal origin. Using a novel carrier for multispecies biofilm development, initial NH4–N concentration variation showed an insignificant effect on SND efficiency. At higher loading, nitrite accumulation due to incomplete denitrification was observed. The effect of CFR was investigated in a range of 20–35%, beyond which non-homogeneous mixing was caused in the reactor. Under controlled DO and temperature of about 5 mg/L and 28 ± 2°C, respectively, an optimum filling ratio of 35% was finalised, resulting in an SND efficiency of 97.9% at 22 h HRT for high influent NH4–N concentration of 500 mg/L. Bacteriological species identification revealed the coexistence of nitrogen-fixing, aerobic nitrifying and anaerobic denitrifying bacteria in the biofilm growing on the biocarrier. Mechanism of SND occurring in aerobic moving bed bioreactors: Laboratory-scale aerobic Moving Bed Bioreactor setup for a continuous study evaluating the influence of operational parameters on SND Occurrence of aerobic and anoxic zones in biofilm grown on the surface of novel carriers due to diffusional gradient of dissolved oxygen [ABSTRACT FROM AUTHOR]

Microalgae-bacteria consortium for wastewater treatment has great potential for use in nutrient removal and biodiesel acquisition. In this study, the effect of four different light/dark regimes (6/18 h , 12/12 h , 18/6 h , 24/0 h) on biomass production and pollutant degradation during the treatment of oilfield wastewater by the algae-bacteria consortium was investigated. The maximum algal biomass (0.2 g/L) and total chlorophyll content (812.76 μgmg−1 cell dry weight−1) were obtained due to an appropriate illumination cycle (18 hlight/6 h dark) with enhanced dissolved oxygen content (5.87 mg/L), thus improving bacterial biomass (0.31 g/L). The ratio of microalgae to bacteria was essentially constant under different light/dark cycles. In addition, the highest removal rates of chemical oxygen demand (55.32%), ammonia nitrogen (50.75%), total nitrogen (64.53%), and total phosphorus (65.97%) were also obtained at the 18/6 h cycle, significantly different from the results of other light/dark cycles. The degradation efficiency of ammonia nitrogen by bacteria increased and then decreased with increasing light duration, while the removal rate of ammonia nitrogen by algae showed the opposite trend. The results indicated that the light and dark regimes had an important influence on the growth of the microalgae-bacteria consortium and their performance in treating oilfield wastewater. [ABSTRACT FROM AUTHOR]

Anastomosis groups belonging to the genus Rhizoctonia are phytopathogenic fungi that affect many agricultural crops and are well distributed globally. Among these, Rhizoctonia solani is the dominant, aggressive, widely distributed and the most extensively studied species within the Rhizoctonia genus because of its dominance as a plant pathogen. However, limited attention has been given to other Rhizoctonia species as they were believed to have little or no role in causing diseases on potatoes. Recently, accumulating information indicated that binucleate Rhizoctonia (BNR), previously considered to be saprophytic, mycorrhizal and even biocontrol agent, is phytopathogenic on many agricultural crops including potato. Up until now, there has been no comprehensive review on BNR. However, there is an intense need to understand its taxonomy, biology, detection, genomics and management, not only due to the growing increased survival and occurrence in various climatic conditions. The limited diagnostic methods, and genomic knowledge make understanding and managing of BNR species difficult. This review outlines the information available in peer‐reviewed literature regarding the BNR anastomosis groups associated with potato diseases, geographical distribution, detection methods, genomics, nomenclature and taxonomical evolution along with some possible management and control strategies. [ABSTRACT FROM AUTHOR]

Rural decentralized domestic wastewater treatment (DDWT) facilities, as an alternative to centralized sewage treatment plants, have been rapidly developed in rural areas worldwide. However, the lack of performance evaluations and operational status assessments of these facilities poses a significant obstacle to advancements in rural domestic wastewater treatment strategies. In the present study, 30 rural DDWT facilities with AO (anoxic/oxic) and AAO (anaerobic/anoxic/oxic) processes were investigated. The results revealed that only two facilities reached the first A-grade discharge standards of China, and twelve facilities met the first B-grade discharge standards for all ten wastewater quality indicators. Low standard-achieving ratios for biochemical oxygen demand (BOD5) (63.3%), total nitrogen (TN) (60.0%), ammonia nitrogen (NH3-N) (63.3%), total phosphorus (TP) (30.0%), suspended solids (SS) (46.7%), and fecal coliforms (FC) (26.7%) were calculated. Thus, it is essential to improve the treatment efficiency for BOD5, TN, NH3-N, TP, SS, and FC for rural wastewater treatment facilities. In addition, the AAO process had a median weighted average removal efficiency of 82.02%, which was better than that of the AO process (72.48%). Minor equipment failure rates, i.e., less than 20%, did not affect the operation of the rural DDWT facilities, since most equipment in the DDWT facilities was backed up. Notably, problems in several areas, e.g., process design, equipment selection, construction, and especially operations, influencing treatment performance should be investigated and proactively addressed. These findings provide specific suggestions for improvements that could benefit the long-term operation and management of rural DDWT facilities. [ABSTRACT FROM AUTHOR]

The presence of nutrients and endocrine-disrupting chemical (EDC) hormones in the aquatic environment can affect wildlife and humans. Sewage treatment using biological processes followed by advanced oxidation processes can be a promising system for EDC removal, however, these have been little investigated in detail in the literature. This study evaluated the removal of nutrients, 17β-estradiol (E2), and 17α-ethynylestradiol (EE2) from sewage using an anaerobic/aerobic/anoxic sequential batch reactor (SBR). Furthermore, the treated sewage generated was subjected to post-treatment using a UV/H2O2 system. Hormones were added to the synthetic sewage only once, and it was submitted to treatment by SBR. The residues of E2 and EE2 were measured in the treated sewage generated by SBR for 13 consecutive cycles. The total removal rate of phosphorus and nitrogen by SBR was in average greater than 75% showing the simultaneous occurrence of nitrification, denitrification, and phosphorus biological removal. Seventeen percentage of the added E2 was detected in treated sewage, but 85% of EE2 was discharged into the same treated after 13 cycles of SBR. Although the literature has indicated the removal of EE2 by sorption and/or biodegradation in biological sewage treatment systems with nitrification, including full-scale ones, this study suggested that this removal has been apparent. The remaining residues of E2 and EE2 were completely degraded by the UV/H2O2 process. The removal of organic matter and nutrients by SBR facilitated the oxidative action of the UV/H2O2 system with lower consumption of peroxide. The integration of these two processes is very promising for EDC removal. [ABSTRACT FROM AUTHOR]

Tanneries generate copious amounts of potentially toxic sludge and effluent from the processing of skins and hides to leather. The effluent requires remediation before discharge to protect the receiving environment. A range of physicochemical methods are used for pre- and post-treatment, but biological secondary remediation remains the most popular choice for the reduction of the organic and macronutrient fraction of tannery effluent. This review provides an update and critical discussion of biological systems used to remediate tannery effluent. While the conventional activated sludge process and similar technologies are widely used by tanneries, they have inherent problems related to poor sludge settling, low removal efficiencies, and high energy requirements. Treatment wetlands are recommended for the passive polishing step of beamhouse effluent. Hybrid systems that incorporate anoxic and/or anaerobic zones with sludge and/or effluent recycling have been shown to be effective for the removal of organics and nitrogenous species at laboratory scale, and some have been piloted. Novel systems have also been proposed for the removal and recovery of elemental sulfur and/or energy and/or process water in support of a circular economy. Full-scale studies showing successful long-term operation of such systems are now required to convince tanneries to modernize and invest in new infrastructure. [ABSTRACT FROM AUTHOR]

One of the most chemically adaptable elements is boron which is found in the periodic table between two groups, i.e., metals and nonmetals and may create more than 16 polymorphs that are bulk and made of connected boron polyhedra. Given that boron and carbon are comparable elements, it has been questioned whether two-dimensional (2D) boron could serve as a conceptual starting point for the construction of other boron nanostructures. Using boron as fundamental building blocks, boron nanosheets were synthesized known as borophenes. Borophene is found to be a crystalline form of atomic monolayer boron which was theoretically first predicted in mid-1990s and experimentally synthesized very recently in 2015. In this work, we studied both armchair and zigzag formation of borophene and presented a comparative analysis of their minimum sub-band energy, effective mean free path En, number of conduction channels Nch, scattering resistance per unit length. The Nch for armchair BNR is 3,2,1 for 22nm, 13nm, 7nm, respectively, which is comparatively more than zigzag BNR. We later proposed Top-Contact BNR (TC-BNR) and Side-Contact BNR (SC-BNR). Our analysis shows that SC-BNR offers 96% less resistance compared to TC-BNR and it is of the order of SC-GNR. Further, if we compare with copper interconnects, BNR is better in terms of performance and copper can be replaced with BNR due to high bulk mean free paths 300nm and 400nm compared to copper’s 40nm. [ABSTRACT FROM AUTHOR]

Synthetic dyes, exceeding 100,000 types on the market and produced at a global scale of over 700,000 tons annually, are extensively used in the textile industry. This industry, a leading contributor to water contamination, relies on dyes like reactive, azo, anthraquinone, and triphenylmethane, resulting in substantial water usage and significant effluent generation. A significant modern challenge is the pollution caused by dye-mixed wastewater, releasing hazardous chemicals into water bodies and posing threats to ecosystems, plants, and human health. Traditionally, physicochemical techniques have addressed textile dye-containing wastewater, but their drawbacks, including cost, inefficiency, and potential secondary pollution, have steered attention towards biological alternatives. Utilizing microorganisms and enzymes, these biological methods, such as microbial cell enzyme immobilization, the biofilm technique, bioreactors, biofuel/bioelectricity production, and genetic engineering, have emerged as promising, cost-effective, and environmentally friendly solutions for efficient dye removal from wastewater. This review paper specifically highlights advanced biological techniques and emphasizes their efficacy in addressing the challenges posed by synthetic textile dyes. Through a systematic review of recent research papers, published results, and observations, this review paper provides insights into emerging biological treatment strategies for effectively removing synthetic textile dyes and contaminants from wastewater. [ABSTRACT FROM AUTHOR]

Hog farm wastewater may require novel biological treatment techniques to improve efficiency and reduce costs. Previous studies combining vermifiltration with downstream hydroponics showed the need for a balanced wastewater nutrient content, particularly the nitrogen-to-phosphorus ratio. Here, a deep-water culture hydroponic system, growing lettuce as model culture, was used to remediate hog farm wastewater after an initial vermifiltration stage, aiming to produce an effluent suitable for irrigation. Supplemented vermifiltered wastewater (SVW) with added nutrients was tested against unsupplemented vermifiltered wastewater (VW) over 35 days, using a synthetic nutrient solution (NS) as a control. Supplementation was shown to improve lettuce growth, light use efficiency, and water use efficiency. Nutrient analysis over time showed a better-balanced phosphorus and nitrogen removal in SVW than in VW; in all treatments nitrogen and phosphorus content was reduced to legally acceptable levels for treated wastewater reuse in irrigation: nitrate 5 mgN L−1 in VW and undetectable in SVW and NS; ammonia undetectable in all treatments; and total phosphorus 2.4 mg L−1 in SVW, 0.9 mg L−1 in NS and undetectable in VW. Coliforms increased in VW and SVW during hydroponic treatment, which should be solved by disinfection. Overall, combining vermifiltration with downstream hydroponic culture proved to be a promising treatment to remediate nutrients in hog farm effluent to make it suitable to be reused for irrigation. [ABSTRACT FROM AUTHOR]

Due to the disposal of different wastewater into the water bodies, the rate of surface water pollution is increasing. The virginia initiative plant (VIP), one of the most efficient and economical wastewater treatment systems, was assessed. The experiments were carried out by a laboratory-scale VIP system used for this study, with a flow rate of 100 L/day and a solid retention time rate estimated at 10 days. The system works on three different ratios for internal rotation (100, 150, and 200%) and three for external rotation (80, 90, and 100%), and the effective volumes were 20, 40, and 60 L for anaerobic, anoxic, and oxic reactors, respectively. The results showed that the VIP system achieved the best removal efficiency of organic matter represented by COD, phosphorous, and ammonia (86, 94, and 93%, respectively). The impact of internal and external rotation ratios was tested by removing COD, phosphorous, and ammonia. The percentages of internal rotation significantly affect the biological removal of nitrates. The relationship between them is inverse, while the percentages of external rotation significantly impact the biological removal process of phosphorus. The relationship between them is positive, whereas the internal and external rotation percentages did not considerably affect the efficiency of removing both ammonia and COD. According to the research results, internal and external rotation ratios enhanced the removal efficiency of phosphorus and nitrates. The VIP system proved to be an effective method for domestic wastewater treatment with a flow conforming to Iraqi standards for draining wastewater with all organic matter, phosphorous, and nitrogenous compounds to rivers.

Wastewater treatment plants (WWTPs) are a point source of nutrients, emit greenhouse gases (GHGs), and produce large volumes of excess sludge. The use of aquatic organisms may be an alternative to the technical post-treatment of WWTP effluent, as they play an important role in nutrient dynamics and carbon balance in natural ecosystems. The aim of this study was therefore to assess the performance of an experimental wastewater-treatment cascade of bioturbating macroinvertebrates and floating plants in terms of sludge degradation, nutrient removal and lowering GHG emission. To this end, a full-factorial experiment was designed, using a recirculating cascade with a WWTP sludge compartment with or without bioturbating Chironomus riparius larvae, and an effluent container with or without the floating plant Azolla filiculoides, resulting in four treatments. To calculate the nitrogen (N), phosphorus (P) and carbon (C) mass balance of this system, the N, P and C concentrations in the effluent, biomass production, and sludge degradation, as well as the N, P and C content of all compartments in the cascade were measured during the 26-day experiment. The presence of Chironomus led to an increased sludge degradation of 44% compared to 25% in the control, a 1.4 times decreased transport of P from the sludge and a 2.4 times increased transport of N out of the sludge, either into Chironomus biomass or into the water column. Furthermore, Chironomus activity decreased methane emissions by 92%. The presence of Azolla resulted in a 15% lower P concentration in the effluent than in the control treatment, and a CO2 uptake of 1.13 kg ha-1 day-1. These additive effects of Chironomus and Azolla resulted in an almost two times higher sludge degradation, and an almost two times lower P concentration in the effluent. This is the first study that shows that a bio-based cascade can strongly reduce GHG and P emissions simultaneously during the combined polishing of wastewater sludge and effluent, benefitting from the additive effects of the presence of both macrophytes and invertebrates. In addition to the microbial based treatment steps already employed on WWTPs, the integration of higher organisms in the treatment process expands the WWTP based ecosystem and allows for the inclusion of macroinvertebrate and macrophyte mediated processes. Applying macroinvertebrate-plant cascades may therefore be a promising tool to tackle the present and future challenges of WWTPs. [ABSTRACT FROM AUTHOR]

This document provides a comprehensive overview of environmental challenges and research areas related to water pollution and treatment. It emphasizes the need to address transportation accidents involving petroleum and optimize petroleum biodegradation. The document also discusses the concern of plastic biodegradation and the potential use of genetically modified microbes for this purpose. Additionally, it addresses the pollution caused by textile dyes and the need for effective removal methods. The document further explores the treatment of metals in water and the role of microorganisms in reducing metal concentrations. It concludes with a summary table of the contributions and research areas covered in the special issue. [Extracted from the article]

Chile has numerous areas that lack sewage collection, including in the capital city. Sanitation in these cases is managed through individual solutions like septic tanks or small wastewater treatment plants (WWTPs) that use biological treatment, usually activated sludge with extended aeration. In general, the design of these systems adheres to the quality standards mandated by regulations for discharge, infiltration, or irrigation. In this scenario, traditional methods like increasing dissolved oxygen (DO) or hydraulic retention time (HRT) were unable to effectively reduce excessive nutrients. Therefore, literature related to nutrient excess and denitrification systems is consulted and reviewed to compile different solutions suitable for the presented issue. Potential solutions were modeled and verified using the free simulation software WRc STOAT. The software accurately predicted the unsatisfactory results of the current setup and provided parameters for the proposed modifications. Experience, precise user definition, influential characteristics, and modeling are essential in the design of WWTPs. [ABSTRACT FROM AUTHOR]

The anaerobic-multistage anoxic/aerobic (A-MAO) process has shown good potential for advanced nitrogen removal in recent years, but its greenhouse gas emissions still need to be fully explored. The effects of the influent distribution and external carbon source sodium acetate on nutrient removal, greenhouse gas emissions, and the microbial community structure in a continuous plug-flow A-MAO reactor fed with real low C/N ratio domestic sewage were investigated. The results showed that altering the allocation of carbon source resulted in average chemical oxygen demand (COD) and total nitrogen (TN) concentration in effluent reduced to 26.10 ± 4.86 and 6.65 ± 1.73 mg/L, respectively. Both operations reduced the emission rate of greenhouse gas. While the addition of external car-bon sources leaded to lower N2O emission rates and higher CO2 and CH4 emission rates. The addition of sodium acetate facilitated nitrification and denitrification processes, thereby leading to a reduction in N2O production. Meanwhile, it spurred the growth of methanogenic bacteria and heterotrophic microorganisms, thus boosting the production of CO2 and CH4. Influent distribution promoted the increase of Bacteroidota, Chloroflexi and Acidobacteriota of the reactor. The enrichment of typical hydrolytic bacteria and glycogen accumulating organisms (GAOs) increased the utilization efficiency of carbon sources in the system after the addition of sodium acetate. The significant increase of typical denitrifying bacteria (DNBs) Azospira reduced the N2O emission during heterotrophic denitrification process, which was considered to be an important functional genus for increasing nitrogen loss in this system. The rational utilization of carbon source makes the difference in metabolism function. The study provides a valuable strategy for comprehensively evaluating the pollutant removal and greenhouse gas emission reduction from the A-MAO process. [ABSTRACT FROM AUTHOR]

To address the issue of insufficient carbon sources in urban sewage, which leads to poor nitrogen removal performance in sewage treatment systems, an anaerobic/anoxic/aerobic (AAO) pilotscale reactor was established. The reactor aimed to treat low C/N (chemical oxygen demand; COD/total nitrogen; TN) municipal wastewater (C/N<5). To enhance nitrogen removal and investigate the mechanism in the AAO process, a Pall ring modified biological suspended filler was introduced to the aerobic zone after achieving partial nitrification and denitrification (PND). The results revealed that the activated sludge-biofilm composite system can be successfully formed within 40 days, with a stable loaded biomass on the membrane at 40.06 mg/g (measured by volatile suspended solids (VSS)/filler). The aerobic zone of the activated sludge-biofilm composite system demonstrated an increase in nitrite accumulation rate (NAR) and simultaneous nitrification and denitrification efficiency (SND), from 60.46% and 19.42% in the initial stage (stage 1) to 69.62% and 46.47% in the stable forming stage (stage 3), respectively. By promoting both PND and SND pathways for nitrogen removal, the effluent from the system exhibited decreased concentrations of ammonia nitrogen (NH4+-N) at 0.11 mg/L and total nitrogen (TN) at 4.55 mg/L, indicating the significant synergistic effect of the biofilm on nitrogen removal. 16S rRNA amplification and sequencing analysis revealed that Proteobacteria was the dominant microorganism in the 60-day biofilm, accounting for 76.12% of the relative abundance. The main ammonia oxidizing bacteria (AOB) were Nitrosomanas (1.77%) and Nitrosococcus (1.69%). Meanwhile, denitrification microbial species were found to have a substantial proportion (29.11%), along with a small amount of Anammox bacteria (Anammoxoglobus, 0.35%) within the biofilm. These sequencing results were consistent with the macroscopic performance of the reactor. Overall, these findings establish a theoretical foundation for enhancing nitrogen removal in the AAO system. [ABSTRACT FROM AUTHOR]

In small populations and scattered communities, wastewater treatment through vegetation filters (VFs), a nature-based solution, has proved to be feasible, especially for nutrient and organic matter removal. However, the presence of pharmaceuticals in wastewater and their potential to infiltrate through the vadose zone and reach groundwater is a drawback in the evaluation of VF performances. Soil amended with readily labile carbon sources, such as woodchips, enhances microbial activity and sorption processes, which could improve pharmaceutical attenuation in VFs. The present study aims to assess if woodchip amendments to a VF's soil are able to abate concentrations of selected pharmaceuticals in the infiltrating water by quantitatively describing the occurring processes through reactive transport modelling. Thus, a column experiment using soil collected from an operating VF and poplar woodchips was conducted, alongside a column containing only soil used as reference. The pharmaceuticals acetaminophen, naproxen, atenolol, caffeine, carbamazepine, ketoprofen and sulfamethoxazole were applied daily to the column inlet, mimicking a real irrigation pattern and periodically measured in the effluent. Ketoprofen was the only injected pharmaceutical that reached the column outlet of both systems within the experimental timeframe. The absence of acetaminophen, atenolol, caffeine, carbamazepine, naproxen and sulfamethoxazole in both column outlets indicates that they were attenuated even without woodchips. However, the presence of 10,11-epoxy carbamazepine and atenolol acid as transformation products (TPs) suggests that incomplete degradation also occurs and that the effect of the amendment on the infiltration of TPs is compound-specific. Modelling allowed us to generate breakthrough curves of ketoprofen in both columns and to obtain transport parameters during infiltration. Woodchip-amended columns exhibited Kd and μw values from one to two orders of magnitude higher compared to soil column. This augmentation of sorption and biodegradation processes significantly enhanced the removal of ketoprofen to over 96%. [ABSTRACT FROM AUTHOR]

Various industrial operations in the dye, fertilizer, pesticide, battery, mining, and chemical industries have been associated with releasing heavy metals in wastewater, such as lead, zinc, copper, arsenic, cadmium, chromium, nickel, and mercury. These metals are dangerous to aquatic life as well as to humans, who may consume them directly or indirectly. Therefore, before being released into open water and land resources, it is necessary to minimize the concentration of toxic ions below the discharge limit. This study used Eichhornia crassipes (Mart.) Solms to remove zinc from wastewater from the electroplating industry in a constructed wetland. Experimental investigations were conducted for removing zinc ions from electroplating industry wastewater using various process parameters such as nutrient dosages, dilution ratios, potential of hydrogen ions, biomasses, and contact times. The outcome of this study revealed that the maximum zinc removal percentage in electroplating industrial wastewater was found for the optimum nutrient dosages of 60 g, dilution ratios of 10, potential hydrogen ion levels of 8, and biomass amounts of 100 g. The maximum zinc removal by Eichhornia crassipes (Mart.) Solms was found to be 88.3 ± 0.6 and 93.4 ± 0.4% at the optimum parameter values for the electroplating industry wastewater and the aqueous solution, respectively, against the optimum contact time of 22 days. This study suggests using this phytoremediation technology to remove all pollutants from industrial wastewater in general, not just wastewater from the electroplating industry. [ABSTRACT FROM AUTHOR]

With the ongoing amendment of the EU legislation on the treatment of urban wastewater, stricter requirements for the removal of pollutants are expected, which calls for the need for innovative wastewater treatment technologies. Biological systems are still the first choice. A survey of typical bioreactors applied in wastewater treatment is presented. The wastewater treatment objective, biochemical environment, and microbial growth are selected as the main criteria for the classification of these bioreactors. Hydraulic and kinetic aspects are considered, along with the advantages and drawbacks of these bioreactors regarding the selection of the appropriate type of reactor; as well, details regarding the operation of reactors are mentioned. The aim of this paper is to provide operators and designers with a brief overview of the selected traditional and advanced processes, reactors, and technologies for nutrient removal from municipal wastewater. The possibilities and limitations in complying with more strict effluent standards are also discussed. Methods of nutrient recovery are added value. From the evaluation of the published papers, we determine that the currently applied traditional methods for nutrient removal have the potential to also convey the expected stricter limits. [ABSTRACT FROM AUTHOR]

This study developed an integrated wastewater treatment system that combines an upflow anaerobic sludge blanket (UASB), downflow hanging non-woven fabric (DHNW), and anaerobic baffled reactor (ABR) to explore the effect of treatment stages on the diversity of microeukaryotic communities. This study aimed to bridge the knowledge gap regarding the influence of integrated system stages on microeukaryotic community diversity. Through 18S rRNA amplicon sequencing, we identified unique microeukaryotic communities across different stages, with the aerobic phase hosting 35.77% of unique amplicon sequence variants (ASVs). The results of principal component analysis (PCA) and non-multidimensional scale analysis (nMDS) demonstrated the significant influence of wastewater treatment on both environmental factors and the microeukaryotic communities. Ciliophora was notably abundant in the effluent (42.09%) and sludge (17.11%). The aerobic stage was dominated by Ochrophyta, a diverse group of algae instrumental in nutrient removal, such as nitrogen and phosphorus, through biological processes. A redundancy analysis (RDA) revealed a positive correlation between chemical and biochemical oxygen demand and Cryptomycotina, highlighting its potential as a bioindicator for treatment efficacy. The detection of protozoan species, such as Acanthamoeba castellanii and Vermamoeba vermiformis, in the outlet stage poses health risks, whereas Cryptosporidium sp. was found in both the inlet and aerobic stages but not in the outlet. Our study reveals the complex nature of microeukaryotic diversity in the wastewater treatment system and its implications for treatment performance and public health. [ABSTRACT FROM AUTHOR]

Objectives] This study was conducted to solve the prominent problems in the treatment of domestic sewage in southern rural areas of China. [Methods] An integrated process treatment mode of anaerobic/anoxic/aerobic moving bed biofilm reactor (A'O-MBBR) was proposed to analyze and study its op- erating effect and influencing factors. [Results] The A'O-MBBR mode had good COD removal efficiency and nitrogen and phosphorus removal performance, and the water quality index of the effluent met the Class A standard of GB181918-2002. This mode is suitable for treating rural domestic sewage, and has high treat- ment effects in different operating periods. In spring, the average removal rates of COD, NH, -N, TN, TP and SS reached (83.53 ± 2.15)%, (89.44 ± 4.97)%, (67.36±18.53)%, (88.22±11.21)% and (91.73±2.25)%, respectively; In the autumn period, the average removal rates of COD, NH, -N, TN, TP and SS were (83.49±2.64)%, (89.26±9.19)%, (66.05±17.00)%, (87.48±9.68)%, and (91.13±2.35)%. [Conclusions] This study provides theoreti- cal reference and technical support for the popularization and application of AO-MBBR integrated process. [ABSTRACT FROM AUTHOR]

Phytohormones have the potential to enhance the nutrient removal efficiency of aquatic plants in wastewater treatment. Here, we investigated the impact of indoleacetic acid (IAA) on nitrogen removal by Hydrocotyle vulgaris Lam during the remediation process of eutrophic water. This investigation involved evaluating the biological indicators of H. vulgaris Lam, the nitrogen salt removal efficiency in eutrophic water, as well as analyzing the bacterial structure and function in both the rhizosphere and eutrophic water surrounding H. vulgaris Lam. The results indicated that surface-sprayed 50 mg/L IAA significantly stimulated the growth of H. vulgaris Lam, including parameters such as blade number, leaf area, petiole length, stem thickness, stem length, and root length of H. vulgaris Lam. Furthermore, exogenous application of IAA significantly accelerated the nitrogen removal of NH4+−N, NO3−−N and total nitrogen (TN) in eutrophic water by promoting the NH4−N uptake of H. vulgaris Lam and NO3−−N denitrification. These findings suggest a potential application for exogenous IAA to enhance the nitrogen removal of H. vulgaris Lam in eutrophication control. [ABSTRACT FROM AUTHOR]

Objective. To indicate the condition of the wastewater treatment with microalgae (WTwM) research. Methodology. The words treatment, wastewater, and microalgae, were entered as keywords in a search under “article title” in SCOPUS. The documents found were saved and exported as a file with a .bb extension. From R Studio, the BIBLIOMETRIX interface was linked to R Statistics. The interface was opened from MOZILLA to import the .bb file. Results. There is a significant increase in the number of papers published since 2013, up to 68 articles in 2022. The authors with the highest number of contributions on the subject are Ivet Ferrer and Joan García. The countries most involved in this issue are China, Spain, India and Brazil; China is the one with the highest number of publications. The WTwM studies in 2023 are concerned with investigating biomass accumulation and nutrient removal as a way to make sustainable use of the process. Conclusions. WTwM is a research topic that is studying and disseminating knowledge since the 80’s. The author who stands out the most is Ivet Ferrer. China has little collaboration with scientists from other countries. The most recent WTwM studies address issues related to biodiesel production and biogas production. The topics to be addressed in future research will be related to the study of temperature, osmotic capacity, pH and O2 levels. [ABSTRACT FROM AUTHOR]

This research explored the use of a granular activated carbon (GAC) column to treat dissolved organics in Combined Sewer Overflows (CSOs), a major river pollutant. The regeneration efficiency of spent GAC was assessed utilizing three distinct methods: biological denitrification, electro-Fenton oxidation, and Sono-Fenton oxidation. Among the six organics tested, sucrose and raw sewage demonstrated the most comparable adsorption characteristics. GAC adsorption factors are multifaceted, involving pore size, surface functional groups, and competing solution substances, rather than just organic matter hydrophobicity. The biological denitrification enabled the utilization of the adsorbed organic matter on spent GAC, consequently reducing the initial NO3-N concentration from 99 mg/L to 8 mg/L over a period of 48 hours. Electro-Fenton treatment revealed marginal performance differences between SUS-SUS and Ti/Pt-Ti/Pt; however, the latter proved superior in terms of electrode stability over prolonged use. A combined strategy employing ultrasound and Fenton treatment at a frequency of 40 kHz yielded marginally higher GAC regeneration efficiency (68.5%) as compared to that at 750 kHz (67.8%). Among all regeneration techniques applied in this investigation, the Sono-Fenton method showed the highest efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute 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.)

To ensure the protection of public health and environmental integrity, while also meeting effluent regulation standards, it is critical to treat leachate due to its composition of hazardous substances before it is introduced into the environment. Pollution from leachate is characterized by several indicators, including COD, BOD5, conductivity, pH, and the presence of various ions such as ammonium, nitrite, nitrate, chloride, and orthophosphate. This research examines the adsorption properties of natural bentonite clay from Nador, located in eastern Morocco, for its efficacy in removing ammonium, nitrate, and nitrite ions from synthetic leachates. We present the outcomes of adsorption experiments utilizing bentonite clay to eradicate these nitrogen-based ions from artificial leachate, using UV adsorption spectroscopy for the measurement of ion concentrations before and after adsorption. Additionally, the study evaluates the efficiency of bentonite clay in adsorption, identifying the optimal amount of clay required for effective pollutant reduction. Our results demonstrate that, following a 24-hour mixing period, the adsorption rates for ammonium, nitrate, and nitrite ions were roughly 48%, 40%, and 85% at 35 °C, and 40%, 15%, and 25% at 25 °C, respectively. These findings suggest that modulation of agitation duration and temperature can significantly improve adsorption efficiency, with elevated temperatures facilitating shorter reaction times and higher adsorption rates for nitrogen ions. Ultimately, the research confirms the potential of bentonite clay as an effective medium for the removal of these contaminants from landfill leachate, offering a promising approach for enhancing environmental sustainability. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) are considered to be hotspots for the spread of antibiotic resistance genes (ARGs). We performed a metagenomic analysis of the raw wastewater, activated sludge and treated wastewater from two large WWTPs responsible for the treatment of urban wastewater in Moscow, Russia. In untreated wastewater, several hundred ARGs that could confer resistance to most commonly used classes of antibiotics were found. WWTPs employed a nitrification/denitrification or an anaerobic/anoxic/oxic process and enabled efficient removal of organic matter, nitrogen and phosphorus, as well as fecal microbiota. The resistome constituted about 0.05% of the whole metagenome, and after water treatment its share decreased by 3–4 times. The resistomes were dominated by ARGs encoding resistance to beta-lactams, macrolides, aminoglycosides, tetracyclines, quaternary ammonium compounds, and sulfonamides. ARGs for macrolides and tetracyclines were removed more efficiently than beta-lactamases, especially ampC, the most abundant ARG in the treated effluent. The removal efficiency of particular ARGs was impacted by the treatment technology. Metagenome-assembled genomes of multidrug-resistant strains were assembled both for the influent and the treated effluent. Ccomparison of resistomes from WWTPs in Moscow and around the world suggested that the abundance and content of ARGs depend on social, economic, medical, and environmental factors. [ABSTRACT FROM AUTHOR]

Background: To assess the influence of serum level of YAP on laboratory examination findings, imaging findings and disease activity of rheumatoid arthritis patients combined cardiovascular disease (RA-CVD). Methods: RA-CVD patients (n = 60), RA-nCVD patients (n = 60) and healthy subjects (n=60) were recruited. Serum levels of YAP in them were detected by qRT-PCR. Their baseline characteristics were analyzed and compared. Disease activity, CVD risk factors and imaging findings in RA-CVD and RA-nCVD patients were evaluated and compared. In addition, potential influences of YAP on disease activity, CVD risk factors and imaging findings in RA-CVD patients were assessed. Results: RA-CVD patients had higher levels of ERS, anti-CCP, RF, HDL-C, CRR FRS, BNR LA, LVs, LVd and cIMT, and lower level of EF in comparison to RA-nCVD patients. Serum level of YAP was higher in RA-CVD patients than that of RA-nCVD patients and healthy subjects. YAP level was positively correlated to DAS28, 4G, CRB PLT, FRS, BNP and cIMT in RA-CVD patients. Conclusions: Serum level of YAP increases in RA-CVD patients. YAP is a potential factor driving the development of CVD in RA patients through regulating inflammatory response, lipid metabolism, glycometabolism and thrombosis. [ABSTRACT FROM AUTHOR]

Historically, 23 freshwater mussel species have been documented from the Buffalo National River (BNR), a 246 km, free-flowing river in northern Arkansas. The potential threats to BNR include land use/land cover changes, eutrophication, recreation, physical habitat changes, and various climate change-related effects. Twelve quantitative mussel bed sites were established and then sampled using a stratified random sampling protocol to evaluate the long-term changes between 2006 and 2020–2021 in population and assemblage characteristics. We compared (1) overall mussel bed persistence, sampling confidence levels and study-wide relative abundances, and compared species' size and size-frequency distributions; (2) 10 overall site assemblage variables using paired t-tests; (3) site-level mean density, richness, and diversity indices using pair-wise Mann–Whitney U statistics; and (4) assemblage composition using Non-Metric Multidimensional Scaling. The major findings included the following: (1) sampling efforts based on a targeted 80% confidence level appears relatively robust, (2) BNR mussel assemblage composition and structure were relatively stable (however, small mussel bed persistence is a concern), (3) 7 of 23 sites were outliers based on freshwater mussel composition and habitat characteristics, and (4) assemblage composition changed with three species declining (Actinonaias ligamentina, Lasmigona costata, and Ptychobranchus occidentalis) and four species increasing (Cambarunio hesperus, Cyclonaias tuberculata, Eurynia dilatata, and Venustaconcha pleasii) between monitoring events. [ABSTRACT FROM AUTHOR]

Rivers in Africa have experienced dire pollution as a result of the poor management of wastewater effluent emanating from water resource recovery facilities (WRRFs). An integrated wastewater resource recovery model was developed and applied to identify ideal wastewater resource recovery technologies that can be used to recover valuable resources from a mixture of wastewater effluents in a case study in the Burgersfort WRRF in the Limpopo province, South Africa. This novel model incorporates the process of biological nutrient removal (BNR) with an extension of conventional methods of resource recovery applicable to wastewater. The assessment of results of effluent quality from 2016 to 2022 revealed that ammonia, chemical oxygen demand, total coliform, fecal coliform, and Escherichia coli levels were critically non-compliant with the permissible effluent guidelines, indicating a stable upward trend in terms of concentrations, and scored a very bad wastewater quality index rating. All variables assessed showed a significant loading, except for orthophosphates, and significant correlations were observed among the variables. The results of the integrated wastewater resource recovery model revealed a high probability of reclaiming recoverable resources such as nutrients, sludge, bioplastics, biofuel, metals, and water from wastewater, which have economic, environmental, and social benefits, thereby improving the effluent quality of a WRRF. [ABSTRACT FROM AUTHOR]