Bradybroberg2553

Discarded plastic wastes in the environment are serious challenges for sustainable waste management and for the delivery of environmental and public health. Plastics in the environment become rapidly colonised by microbial biofilm, and importantly this so-called 'plastisphere' can also support, or even enrich human pathogens. The plastisphere provides a protective environment and could facilitate the increased survival, transport and dissemination of human pathogens and thus increase the likelihood of pathogens coming into contact with humans, e.g., through direct exposure at beaches or bathing waters. However, much of our understanding about the relative risks associated with human pathogens colonising environmental plastic pollution has been inferred from taxonomic identification of pathogens in the plastisphere, or laboratory experiments on the relative behaviour of plastics colonised by human pathogens. There is, therefore, a pressing need to understand whether plastics play a greater role in promoting the survival and dispersal of human pathogens within the environment compared to other substrates (either natural materials or other pollutants). In this paper, we consider all published studies that have detected human pathogenic bacteria on the surfaces of environmental plastic pollution and critically discuss the challenges of selecting an appropriate control material for plastisphere experiments. Whilst it is clear there is no 'perfect' control material for all plastisphere studies, understanding the context-specific role plastics play compared to other substrates for transferring human pathogens through the environment is important for quantifying the potential risk that colonised plastic pollution may have for environmental and public health.COVID-19 pandemic-borne wastes imposed a severe threat to human lives as well as the total environment. Improper handling of these wastes increases the possibility of future transmission. Therefore, immediate actions are required from both local and international authorities to mitigate the amount of waste generation and ensure proper disposal of these wastes, especially for low-income and developing countries where solid waste management is challenging. In this study, an attempt is made to estimate healthcare waste generated during the COVID-19 pandemic in Bangladesh. This study includes infected, ICU, deceased, isolated and quarantined patients as the primary sources of medical waste. Results showed that COVID-19 medical waste from these patients was 658.08 tons in March 2020 and increased to 16,164.74 tons in April 2021. A top portion of these wastes was generated from infected and quarantined patients. Based on survey data, approximate daily usage of face masks and hand gloves is also determined. Probable waste generation from COVID-19 confirmatory tests and vaccination has been simulated. Finally, several guidelines are provided to ensure the country's proper disposal and management of COVID-related wastes.Although the World Health Organization (WHO) announcement released in early March 2020 stated there is no proven evidence that the COVID-19 virus can survive in drinking water or sewage, there has been some recent evidence that coronaviruses can survive in low-temperature environments and in groundwater for more than a week. Some studies have also found SARS-CoV-2 genetic materials in raw municipal wastewater, which highlights a potential avenue for viral spread. A lack of information about the presence and spread of COVID-19 in the environment may lead to decisions based on local concerns and prevent the integration of the prevalence of SARS-CoV-2 into the global water cycle. Several studies have optimistically assumed that coronavirus has not yet affected water ecosystems, but this assumption may increase the possibility of subsequent global water issues. More studies are needed to provide a comprehensive picture of COVID-19 occurrence and outbreak in aquatic environments and more specifically in water resources. As scientific efforts to report reliable news, conduct rapid and precise research on COVID-19, and advocate for scientists worldwide to overcome this crisis increase, more information is required to assess the extent of the effects of the COVID-19 pandemic on the environment. The goals of this study are to estimate the extent of the environmental effects of the pandemic, as well as identify related knowledge gaps and avenues for future research.Macrophyte-dominated ponds, widely distributed in lowland areas, play an important role in nitrogen (N) retention for nonpoint source pollution. However, their impacts on N sources and sinks are scarcely quantified at a watershed scale. This study aimed to investigate N dynamics (sources, sinks, transport, etc.) of macrophyte-dominated ponds and their driving factors in a typical lowland artificial watershed (the Zhong River Watershed) in East China. For this purpose, an hourly-scale pond model (nitrogen dynamic model for macrophyte-dominated ponds, NDP-Pond) was developed, and coupled with a daily scale watershed model (Nitrogen Dynamic Polder model, NDP) to simulate N dynamics, and estimate N retention in macrophyte-dominated ponds. A comparison with the measured water level and total nitrogen (TN) revealed an acceptable model performance (coefficient of determination (R2) > 0.53) for these two models. Based on the N source/sink simulations, we found that 1) macrophyte-dominated ponds showed a large TN removal capacity with a rate of 55%, and a TN loading removal rate of 67 kg·ha-1·yr-1. 2) Denitrification was the main pathway for N removal with a contribution of 57.7%, followed by the uptake of macrophytes (35.8%) and sedimentation (6.5%). 3) The optimal coverage of macrophytes (Alternanthera philoxeroides) to enhance N removal is 2-4 kg·m-2. 4) During the macrophyte-growth period, the TN removal capacity of the pond was higher with a retention time of 1-10 days. Increasing the pond retention time would decrease the N removal efficiency. This study revealed the high value of coupling multiscale models to gain in-depth insights into N retention in macrophyte-dominated pond ecosystems.Electrolytic manganese residue (EMR) contains high concentrations of NH4+ and heavy metals, such as Mn2+, Zn2+, Cu2+, Pb2+, Ni2+ and Co2+, while carbide slag (CS) contains high amount of OH- and CO32-, both posing a serious threat to the ecosystem. In this study, EMR and CS synergistic stabilization/solidification (S/S) was discussed science CS could stabilize or solidify EMR and simultaneously reduce its corrosive. The results showed that after the synergistic S/S for 24 h when liquid-solid ratio was 17.5% and CS dosage was 7%, Mn2+ and NH4+ leaching concentrations of the S/S EMR were below the detection limits (0.02 mg/L and 0.10 mg/L) with a pH value of 8.8, meeting the requirements of the Chinese integrated wastewater discharge standard (GB 8978-1996). Mn2+ was stabilized as MnFe2O4, Mn2SiO4, CaMnSi2O6, and NH4+ escaped as NH3. Zn2+, Cu2+, Pb2+, Ni2+ and Co2+ in EMR can also be stabilized/solidified because of the react with OH- and CO32- in CS. Chemical cost was only $ 0.54 for per ton of EMR synergistic harmless treatment with CS. This study provided a new idea for EMR cost-effective and environment-friendly harmless treatment.To balance the high phosphorus concentration in recirculated solution and the stability of biofilm system, this study explored the performance and mechanism of phosphorus uptake/release for recovering phosphorus from sewage when the phosphorus content in biofilm (Pbiofilm) changed. The results showed that the maximum phosphorus concentration in the concentrated solution reached 171.2 ± 2.5 mg·L-1 in harvest 1st-5th stages. Polyphosphate accumulating organisms (PAOs) performed a metabolic shift from glycogen accumulation metabolism (GAM) to polyphosphate accumulation metabolism (PAM) when Pbiofilm increased at each phosphorus enrichment stage, and more phosphorus was absorbed/released by PAOs. Nevertheless, the release of poly-phosphate from PAOs was inhibited after phosphorus concentration stabilized, and PAOs were unable to absorb phosphorus from wastewater as it reached the phosphorus saturation stage. check details To maintain the stability of the system, phosphorus had to be harvested so that the saturated phosphorus in PAOs was easily released in a new recirculated solution, resulting in adequate storage space for PAOs to absorb phosphorus. Meanwhile, the 31P NMR analysis demonstrated that phosphorus was stored in EPS and cell of PAOs, whereas EPS played a significant role than cell at the anaerobic phase. Particularly, ortho-phosphate was the major component of phosphorus release by EPS and poly-phosphate was the major part of phosphorus release by cell. Furthermore, the change of Pbiofilm had no impact on biofilm characteristics and microbial communities, whereas some PAOs would be enriched, and others that were not suitable for this process would be inhibited with repeated cycles of alternating aerobic/anaerobic operation.Cadmium (Cd) is a well-known testicular toxicant. Blood-testis barrier (BTB), a vital part of testes, which has been reported to be damaged upon Cd exposure. However, the detailed mechanism about Cd-mediated disruption of BTB remains unclear. This study aims to investigate the role of Heme-Regulated Inhibitor (HRI)-responsive mitochondrial stress in Cd-mediated disruption of BTB. Male mice are intraperitoneally injected (i.p.) with melatonin (Mel, a cellular stress antagonist, 5.0 mg/kg) before Cd treatment (i.p., 2.0 mg/kg) for 8 h, and then treated with Cd for 0-48 h. Mouse Sertoli cells are pretreated with Mel (10 μM) for 1 h, and then treated with Cd (10 μM) for 0-24 h. We find that Cd damages the BTB and reduces the Occludin protein, a crucial BTB-related protein via activating p38/matrix metalloproteinase-2 (p38/MMP2) pathway and Integrated Stress Response (ISR). Further experiments reveal that the Heme-Regulated Inhibitor (HRI)-responsive mitochondrial stress is triggered in Cd-treated Sertoli cells. Most importantly, Cd-activated p38 signaling and ISR are regulated by HRI-responsive mitochondrial stress in Sertoli cells. Unexpectedly, we find that melatonin rescues the Cd-mediated disruption of BTB through blocking HRI-responsive mitochondrial stress in testes. Overall, these data indicate that environmental cadmium exposure impairs the BTB through activating HRI-responsive mitochondrial stress in Sertoli cells.Environmental pollution has accelerated and intensified because of the acceleration of industrialization, therefore fabricating excellent materials to remove hazardous pollutants has become inevitable. MXenes as emerging transition metal nitrides, carbides or carbonitrides with high conductivity, hydrophilicity, excellent structural stability, and versatile surface chemistry, become ideal candidates for water purification and environmental remediation. Particularly, MXenes reveal excellent sorption capability and efficient reduction performance for various contaminants of wastewater. In this regard, a comprehensive understanding of the removal behaviors of MXene-based nanomaterials is necessary to explain how they remove various pollutants in water. The eliminate process of MXene-based nanomaterials is collectively influenced by the physicochemical properties of the materials themselves and the chemical properties of different contaminants. Therefore, in this review paper, the synthesis strategies and properties of MXene-based nanomaterials are briefly introduced.