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Ethane, the second most abundant gaseous hydrocarbon in vast anoxic environments, is an overlooked greenhouse gas. Microbial anaerobic oxidation of ethane can be driven by available electron acceptors such as sulfate and nitrate. However, despite nitrite being a more thermodynamically feasible electron acceptor than sulfate or nitrate, little is known about nitrite-driven anaerobic ethane oxidation. In this study, a microbial culture capable of nitrite-driven anaerobic ethane oxidation was enriched through the long-term operation of a nitrite-and-ethane-fed bioreactor. During continuous operation, the nitrite removal rate and the theoretical ethane oxidation rate remained stable at approximately 25.0 mg NO2 -N L-1 d-1 and 11.48 mg C2H6 L-1 d-1, respectively. Batch tests demonstrated that ethane is essential for nitrite removal in this microbial culture. Metabolic function analysis revealed that a species affiliated with a novel genus within the family Rhodocyclaceae, designated as 'Candidatus Alkanivoras nitrosoreducens', may perform the nitrite-driven anaerobic ethane oxidation. In the proposed metabolic model, despite the absence of known genes for ethane conversion to ethyl-succinate and succinate-CoA ligase, 'Ca. A. nitrosoreducens' encodes a prospective fumarate addition pathway for anaerobic ethane oxidation and a complete denitrification pathway for nitrite reduction to nitrogen. These findings advance our understanding of nitrite-driven anaerobic ethane oxidation, highlighting the previously overlooked impact of anaerobic ethane oxidation in natural ecosystems.
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The coupling between anammox and nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) has been considered a sustainable technology for nitrogen removal from sidestream wastewater and can be implemented in both membrane biofilm reactor (MBfR) and granular bioreactor. However, the potential influence of the accompanying hydrogen sulfide (H2S) in the anaerobic digestion (AD)-related methane-containing mixture on anammox/n-DAMO remains unknown. To fill this gap, this work first constructed a model incorporating the C/N/S-related bioprocesses and evaluated/calibrated/validated the model using experimental data. The model was then used to explore the impact of H2S on the MBfR and granular bioreactor designed to perform anammox/n-DAMO at practical levels (i.e., 0â¼5% (v/v) and 0â¼40 g/S m3, respectively). The simulation results indicated that H2S in inflow gas did not significantly affect the total nitrogen (TN) removal of the MBfR under all operational conditions studied in this work, thus lifting the concern about applying AD-produced biogas to power up anammox/n-DAMO in the MBfR. However, the presence of H2S in the influent would either compromise the treatment performance of the granular bioreactor at a relatively high influent NH4+-N/NO2--N ratio (e.g., >1.0) or lead to increased energy demand associated with TN removal at a relatively low influent NH4+-N/NO2--N ratio (e.g., <0.7). Such a negative effect of the influent H2S could not be attenuated by regulating the hydraulic residence time and should therefore be avoided when applying the granular bioreactor to perform anammox/n-DAMO in practice.
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Reatores Biológicos , Sulfeto de Hidrogênio , Metano , Nitratos , Nitritos , Oxirredução , Sulfeto de Hidrogênio/metabolismo , Anaerobiose , Metano/metabolismo , Nitratos/metabolismo , Eliminação de Resíduos Líquidos/métodos , Nitrogênio/metabolismo , Águas Residuárias/químicaRESUMO
'Candidatus Methanoperedens nitroreducens' is an archaeal methanotroph with global importance that links carbon and nitrogen cycles and great potential for sustainable operation of wastewater treatment. It has been reported to mediate the anaerobic oxidation of methane through a reverse methanogenesis pathway while reducing nitrate to nitrite. Here, we demonstrate that 'Ca. M. nitroreducens' reduces ferric iron forming ammonium (23.1 %) and nitrous oxide (N2O, 46.5 %) from nitrate. These results are supported with the upregulation of genes coding for proteins responsible for dissimilatory nitrate reduction to ammonium (nrfA), N2O formation (norV, cyt P460), and multiple multiheme c-type cytochromes for ferric iron reduction. Concomitantly, an increase in the N2O-reducing SJA-28 lineage and a decrease in the nitrite-reducing 'Candidatus Methylomirabilis oxyfera' are consistent with the changes in 'Ca. M. nitroreducens' end products. These findings demonstrate the highly flexible physiology of 'Ca. M. nitroreducens' in anaerobic ecosystems with diverse electron acceptor conditions, and further reveals its roles in linking methane oxidation to global biogeochemical cycles. 'Ca. M. nitroreducens' could significantly affect the bioavailability of nitrogen sources as well as the emission of greenhouse gas in natural ecosystems and wastewater treatment plants.
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Compostos de Amônio , Metano , Nitratos , Óxido Nitroso , Oxirredução , Metano/metabolismo , Óxido Nitroso/metabolismo , Compostos de Amônio/metabolismo , Anaerobiose , Nitratos/metabolismo , Compostos Férricos/metabolismoRESUMO
Aerobic methanotrophs establish a symbiotic association with denitrifiers to facilitate the process of aerobic methane oxidation coupled with denitrification (AME-D). However, the symbiosis has been frequently observed in hypoxic conditions continuing to pose an enigma. The present study has firstly characterized an electrically induced symbiosis primarily governed by Methylosarcina and Hyphomicrobium for the AME-D process in a hypoxic niche caused by Comammox Nitrospira. The kinetic analysis revealed that Comammox Nitrospira exhibited a higher apparent oxygen affinity compared to Methylosarcina. While the coexistence of comammox and AME-D resulted in an increase in methane oxidation and nitrogen loss rates, from 0.82 ± 0.10 to 1.72 ± 0.09 mmol CH4 d-1 and from 0.59 ± 0.04 to 1.30 ± 0.15 mmol N2 d-1, respectively. Furthermore, the constructed microbial fuel cells demonstrated a pronounced dependence of the biocurrents on AME-D due to oxygen competition, suggesting the involvement of direct interspecies electron transfer in the AME-D process under hypoxic conditions. Metagenomic and metatranscriptomic analysis revealed that Methylosarcina efficiently oxidized methane to formaldehyde, subsequently generating abundant NAD(P)H for nitrate reduction by Hyphomicrobium through the dissimilatory RuMP pathway, leading to CO2 production. This study challenges the conventional understanding of survival mechanism employed by AME-D symbionts, thereby contributing to the characterization responsible for limiting methane emissions and promoting nitrogen removal in hypoxic regions.
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Metano , Nitrogênio , Oxigênio , Simbiose , Nitrogênio/metabolismo , Metano/metabolismo , Oxigênio/metabolismo , Oxirredução , DesnitrificaçãoRESUMO
Anode modification is an effective strategy for enhancing the electrochemical performance of microbial fuel cell (MFC). However, the impacts of the modified materials on anode biofilm development during MFC operation have been less studied. We prepared a novel PDA-Fe3O4-CF composite anode by coating original carbon felt anode (CF) with polydopamine (PDA) and Fe3O4 nanoparticles. The composite anode material was characterized by excellent hydrophilicity and electrical conductivity, and the anodic biofilm exhibited fast start-up, higher biomass, and more uniform biofilm layer after MFC operation. The MFC reactor assembled with the composite anode achieved a maximum power density of 608 mW m-2 and an output voltage of 586 mV, which were 316.4% and 72.4% higher than the MFC with the original CF anode, respectively. Microbial community analysis indicated that the modified anode biofilm had a higher relative abundance of exoelectrogen species in comparison to the unmodified anode. The PICRUSt data revealed that the anodic materials may affect the bioelectrochemical performance of the biofilm by influencing the expression levels of key enzyme genes involved in biofilm extracellular polymer (EPS) secretion and extracellular electron transfer (EET). The growth of the anodic biofilm would exert positive or negative influences on the efficiency of electricity production and electron transfer of the MFCs at different operating stages. This work expands the knowledge of the role that anodic materials play in the development and electrochemical performance of anodic biofilm in MFCs.
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Fontes de Energia Bioelétrica , Indóis , Polímeros , Carbono/química , Fibra de Carbono , Eletricidade , Eletrodos , BiofilmesRESUMO
Cancer-related fatigue (CRF) is a widespread symptom with high prevalence in cancer patients, seriously affecting their quality of life. In the context of precision care, constructing machine learning-based prediction models for early screening and assessment of CRF is beneficial to this situation. To further understand the predictors of CRF for model construction, we conducted a comprehensive search in PubMed, Web of Science, Embase, and Scopus databases, combining CRF with predictor-related terms. A total of 27 papers met the inclusion criteria. We evaluated the above studies into three subgroups following the predisposing, precipitating, and perpetuating (3P) factor model. (1) Predisposing factors-baseline fatigue, demographic characteristics, clinical characteristics, psychosocial traits and physical symptoms. (2) Precipitating factors-type and stage of chemotherapy, inflammatory factors, laboratory indicators and metabolic changes. (3) Perpetuating factors-a low level of physical activity and poorer nutritional status. Future research should prioritize large-scale prospective studies with emerging technologies to identify accurate predictors of CRF. The assessment and management of CRF should also focus on the above factors, especially the controllable precipitating factors, to improve the quality of life of cancer survivors.
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Nitrate/nitrite-dependent anaerobic oxidation of methane (n-DAMO) is a recently discovered process, which provides a sustainable perspective for simultaneous nitrogen removal and greenhouse gas emission (GHG) mitigation by using methane as an electron donor for denitrification. However, the engineering roadmap of the n-DAMO process is still unclear. This work constitutes a state-of-the-art review on the classical and most recently discovered metabolic mechanisms of the n-DAMO process. The versatile combinations of the n-DAMO process with nitrification, nitritation, and partial nitritation for nitrogen removal are also clearly presented and discussed. Additionally, the recent advances in bioreactor development are systematically reviewed and evaluated comprehensively in terms of methane supply, biomass retention, membrane requirement, startup time, reactor performance, and limitations. The key issues including enrichment and operation strategy for the scaling up of n-DAMO-based processes are also critically addressed. Moreover, the challenges inherent to implementing the n-DAMO process in practical applications, including application scenario recognition, GHG emission mitigation, and operation under realistic conditions, are highlighted. Finally, prospects as well as opportunities for future research are proposed. Overall, this review provides a roadmap for potential applications and further development of the n-DAMO process in the field of wastewater treatment.
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Compostos de Amônio , Nitratos , Nitratos/metabolismo , Nitritos/metabolismo , Nitrificação , Anaerobiose , Metano , Desnitrificação , Compostos de Amônio/metabolismo , Oxirredução , Reatores Biológicos , Nitrogênio/metabolismoRESUMO
Nitrite-dependent anaerobic methane oxidizing (n-DAMO) bacteria generally convert nitrite to dinitrogen and bypass the nitrous oxide (N2O) formation step. However, N2O is often detected in n-DAMO bacteria dominated cultures and it remains an open question as to the microbial origin of N2O in these enrichments. Using a stable nitrite consuming microbial community enriched for n-DAMO bacteria, we demonstrated that N2O production was coupled to methane oxidation and the higher initial nitrite concentrations led to increased quantities of N2O being formed. Moreover, continuous exposure of the enrichment culture to about 5 mg of N L-1 nitrite resulted in constant N2O being produced (12.5% of nitrite was reduced to N2O). Metatranscriptomic analyses revealed that nitrite reductase (nirS) and nitric oxide reductase (norZ) transcripts from n-DAMO bacteria increased in response to nitrite exposure. No other bacteria significantly expressed nor genes under these conditions, suggesting n-DAMO bacteria are responsible for N2O being produced. In a 35-day bioreactor experiment, N2O produced by the n-DAMO bacteria accumulated when nitrite was in excess; this was found to be up to 3.2% of the nitrogen that resulted from nitrite removal. Together, these results suggested that excess nitrite is an important driver of N2O production by n-DAMO bacteria. To this end, proper monitoring and control of nitrite levels in wastewater treatment plants would be effective strategies for mitigating N2O emissions to the atmosphere.
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Methylococcaceae , Nitritos , Anaerobiose , Óxido Nitroso , Oxirredução , Metano , Reatores Biológicos/microbiologia , DesnitrificaçãoRESUMO
OBJECTIVE: This review aimed to summarize the use of machine learning for predicting the potential benefits of stroke rehabilitation treatments, to evaluate the risk of bias of predictive models, and to provide recommendations for future models. MATERIALS AND METHODS: This systematic review was conducted in accordance with the PRISMA statement and the CHARMS checklist. The PubMed, Embase, Cochrane Library, Scopus, and CNKI databases were searched up to April 08, 2023. The PROBAST tool was used to assess the risk of bias of the included models. RESULTS: Ten studies within 32 models met our inclusion criteria. The optimal AUC value of the included models ranged from 0.63 to 0.91, and the optimal R2 value ranged from 0.64 to 0.91. All of the included models were rated as having a high or unclear risk of bias, and most of them were downgraded due to inappropriate data sources or analysis processes. DISCUSSION AND CONCLUSION: There remains much room for improvement in future modeling studies, such as high-quality data sources and model analysis. Reliable predictive models should be developed to improve the efficacy of rehabilitation treatment by clinicians.
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Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/terapia , Viés , Aprendizado de MáquinaRESUMO
BACKGROUND: Wound healing is a complex and dynamic process that involves a series of cellular and molecular events. Mesenchymal stem cells (MSCs) and their exosomes (MSC-Exos) have crucial functions in cutaneous wound healing. MiR-17-92 is a multifunctional microRNA (miRNA) cluster that plays vital roles in tissue development and tumor angiogenesis. This study aimed to explore the function of miR-17.92 in wound healing as a component of MSC-Exos. METHODS: Human MSCs were cultured in serum-free medium, and exosomes were collected by ultracentrifugation. The levels of miR-17-92 in MSCs and MSC-Exos were determined by quantitative real-time polymerase chain reaction. MSC-Exos were topically applied to full-thickness excision wounds in the skin of miR-17-92 knockout (KO) and wild-type (WT) mice. The proangiogenic and antiferroptotic effects of MSC-Exos overexpressing miR-17-92 were assayed by evaluating the relative levels of angiogenic and ferroptotic markers. RESULTS: MiRNA-17-92 was found to be highly expressed in MSCs and enriched in MSC-Exos. Moreover, MSC-Exos promoted the proliferation and migration of human umbilical vein endothelial cells in vitro. KO of miR-17-92 effectively attenuated the promotion of wound healing by MSC-Exos. Furthermore, exosomes derived from miR-17-92-overexpressing human umbilical cord-derived MSCs accelerated cell proliferation, migration, angiogenesis, and enhanced against erastin-induced ferroptosis in vitro. miR-17-92 plays a key role in the protective effects of MSC-Exos against erastin-induced ferroptosis in HUVECs CONCLUSION: These findings suggest that miR-17-92 participates in the repair ability of MSC-Exos and that miR-17-92-overexpressing exosomes may represent a new strategy for cutaneous wound repair.
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Exossomos , Ferroptose , Células-Tronco Mesenquimais , MicroRNAs , Animais , Humanos , Camundongos , Exossomos/genética , Células Endoteliais da Veia Umbilical Humana , MicroRNAs/genética , MicroRNAs/farmacologia , Cicatrização/genéticaRESUMO
Nitrite-dependent anaerobic methane oxidation (n-DAMO) has been demonstrated to play important roles in the global methane and nitrogen cycle. However, despite diverse n-DAMO bacteria widely detected in environments, little is known about their physiology for microbial niche differentiation. Here, we show the microbial niche differentiation of n-DAMO bacteria through long-term reactor operations combining genome-centered omics and kinetic analysis. With the same inoculum dominated by both species "Candidatus Methylomirabilis oxyfera" and "Candidatus Methylomirabilis sinica", n-DAMO bacterial population was shifted to "Ca. M. oxyfera" in a reactor fed with low-strength nitrite, but shifted to "Ca. M. sinica" with high-strength nitrite. Metatranscriptomic analysis showed that "Ca. M. oxyfera" harbored more complete function in cell chemotaxis, flagellar assembly, and two-component system for better uptake of nitrite, while "Ca. M. sinica" had a more active ion transport and stress response system, and more redundant function in nitrite reduction to mitigate nitrite inhibition. Importantly, the half-saturation constant of nitrite (0.057 mM vs 0.334 mM NO2-) and inhibition thresholds (0.932 mM vs 2.450 mM NO2-) for "Ca. M. oxyfera" vs "Ca. M. sinica", respectively, were highly consistent with genomic results. Integrating these findings demonstrated biochemical characteristics, especially the kinetics of nitrite affinity and inhibition determine niche differentiation of n-DAMO bacteria.
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Metano , Nitritos , Anaerobiose , Cinética , Dióxido de Nitrogênio , Bactérias/genética , OxirreduçãoRESUMO
Constructed wetlands (CWs) amended with biochar have attracted much attention for nitrate removal treating secondary effluent. However, little is acknowledged about the linkage among the nitrate removal performance, microbial metabolic pathway of nitrate, and biochar properties. Herein, biochars pyrolyzed under 300 °C, 500 °C, and 700 °C (BC300, BC500, and BC700, respectively) were used in CWs to reveal the relationship. Results showed that CWs amended with BC300 (59.73%), BC500 (53.27%), and BC700 (49.07%) achieved higher nitrogen removal efficiency, compared with the control (39.51%). Metagenomic analysis showed that biochars could enrich the genes, which encoded key enzymes (adenosine triphosphate production, and electrons generation, transportation, and consumption) involved in carbon and nitrate metabolism. Further, biochar pyrolyzed under lower temperature, with higher oxygen content, molar O/C ratio, and the electron donating capacity, in CWs could obtain higher nitrate removal efficiency. Overall, this research offers new understandings for the promotion of denitrification in CWs amended with biochar.
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Desnitrificação , Nitratos , Áreas Alagadas , Carvão Vegetal , Nitrogênio , Redes e Vias Metabólicas , Eliminação de Resíduos Líquidos/métodosRESUMO
PURPOSE: Cancer-related fatigue (CRF) is the most common symptom in cancer patients and may interfere with patients' daily activities and decrease survival rate. However, the etiology of CRF has not been identified. Diagnosing CRF is challenging. Thus, our study aimed to develop a CRF prediction model in cancer patients, using data that healthcare professionals routinely obtained from electronic health records (EHRs) based on the 3P model and externally validate this model in an independent dataset collected from another hospital. METHODS: Between April 2022 and September 2022, a cross-sectional study was conducted on adult cancer patients at two first-class tertiary hospitals in China. Data that healthcare professionals routinely obtained from electronic health records (EHRs) based on the 3P model were collected. The outcome measure was according to ICD-10 diagnostic criteria for CRF. Data from one hospital (n = 305) were used for model development and internal validation. An independent data set from another hospital (n = 260) was utilized for external validation. logistic regression, random forest (RF), Naive Bayes (NB), and extreme gradient boosting (XGBoost) were constructed and compared. The model performance was evaluated in terms of both discrimination and calibration. RESULTS: The prevalence of CRF in the two centers was 57.9% and 56.1%, respectively. The Random Forest model achieved the highest AUC of 0.86 among the four types of classifiers in the internal validation. The AUC of RF and NB were above 0.7 in the external validation, suggesting that the models also have an acceptable generalization ability. CONCLUSIONS: The incidence of CRF remains high and deserves more attention. The fatigue prediction model based on the 3P theory can accurately predict the risk of CRF. Nonlinear algorithms such as Random Forest and Naive Bayes are more suitable for diagnosing and evaluating symptoms.
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Detecção Precoce de Câncer , Neoplasias , Humanos , Adulto , Estudos Transversais , Teorema de Bayes , Aprendizado de Máquina , Neoplasias/complicações , Neoplasias/epidemiologiaRESUMO
Recently, the nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) processes have become a research hotspot in the field of wastewater treatment. The n-DAMO processes could not only mitigate direct and indirect carbon emissions from wastewater treatment plants but also strengthen biological nitrogen removal. However, the applications of n-DAMO-based biotechnologies face practical difficulties mainly caused by the distinctive properties of n-DAMO microorganisms and the limited/availability of methane with poor solubility. In this sense, the choice of bioreactors will play important roles that influence the growth and functioning of n-DAMO microorganisms, thus enabling dedicated development of the n-DAMO processes and efficient applications of n-DAMO-based biotechnologies. Therefore, this paper aims to discuss the three commonly-applied types of bioreactors, covering the individual working principle and state-of-the-art removal performance of nitrogen as well as dissolved methane observed when adopted for n-DAMO-based biotechnologies. With noted limitations for each bioreactor type, several key perspectives were proposed which hopefully would inspire future investigation and practical applications of the n-DAMO processes.
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Compostos de Amônio , Metano , Águas Residuárias , Nitratos , Nitritos , Anaerobiose , Desnitrificação , Reatores Biológicos , Nitrogênio , Oxirredução , Óxidos de NitrogênioRESUMO
Riparian sediment is the last barrier preventing contaminants from polluting aquatic ecosystems. Recently, microplastics (MPs) have frequently been found in sediments. However, the MP aging process and its impact on sediments remain unknown. This study aimed to identify the key driving factors and mechanisms of riparian sediment on MPs aging behavior. The results showed that MPs surface suffered heavy breakage and the oxygen-to-carbon ratio of MPs increased by 268 % after accumulation in sediment for 214 d. The carbonyl index revealed that the degree of MP aging driven by dissolved organic matter (DOM) was 6.7-83.6 % greater than that of colloids, indicating that DOM was the key sediment fraction driving MP aging. Sunlight was an important environmental factor that enhanced MPs aging by sediment fractions, because photo-irradiated DOM produced hydroxyl and superoxide radicals to damage the MPs structure. Benzoic acid, dibenzoylmethane, and 4-heptyl-4,6-diphenyl-tetrahydro-pytan-2-one were the main products during the MP aging process under the interaction of sunlight and DOM, which showed acute toxicity to aquatic organisms and caused more severe toxicity during the chronic period. These results clearly clarify the behavior and environmental risk of MPs after accumulation in sediment, providing guide information to control MP pollution in the riparian zone.
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Microplásticos , Poluentes Químicos da Água , Microplásticos/toxicidade , Plásticos/química , Matéria Orgânica Dissolvida , Ecossistema , Poluentes Químicos da Água/química , ColoidesRESUMO
Riverbanks play the key role in ammonium removal from runoff entering river. Currently, microplastics (MPs) are frequently detected in riverbanks receiving urban and agricultural runoff. Nevertheless, the effect of MPs accumulation on ammonium removal in riverbanks is still unknown. We utilized sediment flow-through reactors to investigate the impact and mechanism of MPs accumulation on ammonium removal in riverbanks. These results revealed that MPs accumulation decreased ammonium removal in sediment by 8.2 %-12.8 % resulting from the reduction in nitrifier abundance (Nitrososphaera and Nitrososphaeraceae) and genes encoding ammonium and hydroxylamine oxidation (amoA, amoB, amoC, and hao) by MPs accumulation. Furthermore, MPs accumulation decreased the substrate and gene abundance of hydroxylamine oxidation process to reduce N2O emission (16.3 %-34.3 %). Notably, mathematic model verified that sediment physical properties changed by MPs accumulation were direct factors affecting ammonium removal in riverbank. It was suggested that both the biotoxicity of MPs and sediment physical properties should be considered in the ammonium removal process. To summarize, this study for the first time comprehensively clarifies the impact of MPs on the ammonium removal capacity of riverbanks, and provides information for taking measures to protect the ecological function of the riverbank and river ecosystem from MPs and ammonium pollution.
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Compostos de Amônio , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental/métodos , Hidroxilaminas , Microplásticos , Plásticos , Poluentes Químicos da Água/análiseRESUMO
Anaerobic ammonium oxidation (anammox) and nitrification, two common biological ammonium oxidation pathways, are critical for the microbial nitrogen cycle. Short chain alkanes (C2-C8) have been well-known as inhibitors for nitrification through interaction with the ammonia monooxygenase, while whether these alkanes affect anammox is an open question. Here, this work demonstrated significant inhibition of ethane on anammox and revealed the inhibitory mechanism. The acute inhibition of ethane on anammox was concentration-dependent and reversible; 0.86 mM dissolved ethane caused 50% inhibition (IC50), and 1.72 mM ethane almost completely inhibited anammox. After long-term exposure to 0.09 mM ethane for 30 days, the ammonium (nitrite) removal rate dropped from 202 (267) mg N L-1 d-1 to 1 (1) mg N L-1 d-1, and the abundance of anammox bacteria decreased from 61.9% to 9.5%. The intercellular ammonium concentration of anammox bacteria decreased after ethane exposure, while metatranscriptome analysis showed significant upregulation of genes for ammonium transport of anammox bacteria. Thus, ethane could suppress ammonium uptake resulting in the inhibition of anammox activities. As ethane is the second most prevalent alkane after methane in various anoxic environments, ethane may have an important effect on the nitrogen cycle driven by anammox that should be investigated in future research.
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Compostos de Amônio , Nitritos , Compostos de Amônio/metabolismo , Anaerobiose , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Desnitrificação , Etano , Metano/metabolismo , Nitritos/metabolismo , Nitrogênio/análise , OxirreduçãoRESUMO
BACKGROUND: Graft-versus-host disease (GVHD) is a fatal complication of hematopoietic stem cell transplantation and is an enormous burden on the patient economy and related health systems. Nevertheless, only a few bibliometric studies have examined the direction of research and the major findings within the field. METHODS: Statistical and visualization bibliometric analysis was performed in April 2021. Our research data were retrieved from the Web of Science using an advanced search strategy. We then used bibliometric analysis to determine the current general research direction and trend of publications and established the most prolific and distinguished authors, institutions, countries, funding agencies, and keywords in GVHD research. We employed VOSviewer (Leiden University, Leiden, Netherlands), Microsoft Excel (Microsoft, Redmond, State of Washington), and GunnMap (https://lert.co.nz/map/) to retrieve, integrate, and visualize the results. RESULTS: Overall, 15,378 publications from 500 journals were extracted from the Institute for Scientific Information (ISI) Web of Science Core Collection database based on our analysis, of which the United States and the Fred Hutchinson Cancer Research Center were the most prolific countries and institutions, respectively. Moreover, we identified future research trends and the current status of GVHD research based on the top 10 most cited articles. Finally, influential authors' analysis demonstrated that Blazar, BR were both the most productive and most cited among all authors. CONCLUSION: Our study provides an exhaustive and objective overview of the current status of GVHD research. This information would be highly beneficial to anyone seeking information on GVHD and would serve as a reference guide for researchers aiming to conduct further GVHD research.
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Doença Enxerto-Hospedeiro , Publicações , Bibliometria , Eficiência , Humanos , Países BaixosRESUMO
AIM: The primary goal of this analysis is to determine the effectiveness of blended learning versus traditional face-to-face teaching in nursing education from the three aspects of knowledge, skills and satisfaction. BACKGROUND: With the rapid development of health care, traditional teaching has been unable to meet the learning needs of nursing education. With the development of Internet technology, blended learning seems to be a new available choice to solve the current predicament. However, the effectiveness of blended learning is still controversial. In addition, most studies have primarily evaluated the teaching effect unilaterally. DESIGN: Systematic review and meta-analysis. METHODS: We searched PubMed, Embase, Web of Science, CINAHL and the Cochrane Library for publications in English from inception to April 2021. Two researchers independently screened the eligibility of each publication and extracted the data. The Cochrane risk-of-bias tool and the MINORS (methodological items for non-randomized studies) were used to evaluate the quality of the studies. The statistical heterogeneity was analyzed by the meta-regression and subgroup analysis. Publication bias was assessed by Egger's test. RESULTS: The search strategy identified a total of 3682 potentially relevant articles. We finally included 13 randomized controlled trials (RCTs) and 12 quasi-experimental studies (QRs), with a total of 2706 nursing students. The meta-analysis results showed that blended learning is more effective than traditional teaching in terms of knowledge, skill performance and learning satisfaction (SMD=0.64, z = 3.237, p = 0.001; SMD = 0.37, z = 2.58, p = 0.010; SMD = 0.32, z = 2.347, p = 0.019). Egger's test showed no significant publication bias. In addition, sensitivity analysis suggested that the results are relatively reliable. Through subgroup analysis and meta regression, we found that although the heterogeneity could not be significantly reduced or eliminated, the publication year, the study design and the duration of the intervention time and the number of items in the intervention may be the potential factors affecting heterogeneity of knowledge and learning satisfaction. CONCLUSIONS: The research results showed that blended learning may be an effective teaching strategy and appears to have excellent long-term developmental potential. Although its initial construction may require specific investment to improve the teaching resources and standardize the design of blended learning, in the long term, this new teaching strategy can not only improve nursing students' professional ability and learning satisfaction but also save nursing education resources to promote the balanced development of nursing education. The results of this study can lay a foundation for establishing standardized blended teaching strategies and evaluation indicators in the future.
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Educação a Distância , Educação em Enfermagem , Estudantes de Enfermagem , Competência Clínica , Educação a Distância/métodos , Educação em Enfermagem/métodos , Humanos , Aprendizagem , EnsinoRESUMO
To carry out the translation and cultural adaptation of the attitude towards pressure ulcer prevention instrument for use in Chinese and to analyse the validity and reliability of the adapted version of the questionnaire. In this quantitative, descriptive, cross-sectional study, after translation of the questionnaire from English to Chinese, back-translation, and assessment of equivalence between the original and back-translated version by an expert panel, the Chinese version instrument was assessed by a convenience sample of registered nurses in several hospitals in cities of China. The internal consistency and content validity of the instrument was tested, and a confirmatory factor analysis was also performed. Confirmatory factor analysis showed that the goodness of fit of the five-factor model after the scale localization was not ideal. Therefore, confirmatory factor analysis is performed to obtain the three-factor solution of comparative fit index, goodness-of-fit index, and adjusted goodness-of-fit index reaching the acceptable standard. The instrument score of nurses with wound care certification was significantly higher than that of nurses without wound care special certification. The adapted version of the instrument for Chinese nurses can be used as a tool to measure attitudes towards pressure injury prevention.