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1.
Chemosphere ; 345: 140494, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37863210

ABSTRACT

Nitrogen (N) removal from wastewater is essential, but it a process that demands a substantial amount of energy. Therefore, there is an urgent need to develop treatment processes that can conserve and use energy effectively. This study investigated the potential of a single chamber bio-electrochemical system (BES) for ammonium (NH4+) removal. Various NH4+:NO2- ratios (1:1, 1:0.5, and 1:0) were tested at an applied potential of 0.4 V vs. Ag/AgCl. Potential in the reactors (R-1, R-2, and R-3) significantly improved NH4+ removal efficiencies. Specifically, R-1, R-2, and R-3 exhibited removal efficiencies of 68.12%, 64.22%, and 57.86%, respectively. NH4+ oxidation in R-3 involved using a carbon brush electrode as an electron acceptor. Significant electric charge generation was observed in all reactors (R-1, R-2, and R-3) during NH4+ removal. Particularly, the use of a carbon brush as an electron acceptor in R-3 resulted in higher electric charge generation compared to those in R-1 and R-2, where NO2- served as an electron acceptor. Upon NH4+ removal and concurrent electric charge generation, nitrate (NO3-) accumulation was observed in reactors with applied potential (R-1, R-2, and R-3), demonstrating greater accumulation compared to reactors without potential (R-7, R-8, and R-9). The mechanism involves ammonium oxidizing bacteria (AOB) oxidizing NH4+ to NO2-, which is then further oxidized by nitrite-oxidizing bacteria (NOB) to NO3-. ANAMMOX bacteria could directly produce N2 from NH4+ and NO2- or NH4+ could be oxidized to N2 through extracellular electron transfer (EET). A carbon brush electron acceptor reduces NO2- requirement by 1.65 g while enhancing NH4+ oxidation efficiency. This study demonstrates the potential of mixed culture ANAMMOX granules for efficient NO2-free NH4+ removal.


Subject(s)
Ammonium Compounds , Nitrites , Anaerobiosis , Anaerobic Ammonia Oxidation , Nitrogen Dioxide , Oxidation-Reduction , Bacteria , Oxidants , Carbon , Bioreactors/microbiology , Nitrogen , Denitrification
2.
Chemosphere ; 339: 139776, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37567277

ABSTRACT

Biological nitrogen removal (BNR) is essential for the treatment of nitrogen-containing wastewater. However, the requirement for aeration and the addition of external carbon sources, resulting in greenhouse gas emissions and additional costs, are disadvantages of the traditional BNR process. Alternative technologies have been devised to overcome these drawbacks. Bioelectrochemical nitrogen removal (BENR) has been proposed for efficient nitrogen removal, demonstrating flexibility and versatility. BENR can be performed by combining nitrification, denitrification, anaerobic ammonium oxidation (ANAMMOX), or organic carbon oxidation. Bioelectrochemical-ANAMMOX (BE-ANAMMOX) is the most promising method for nitrogen removal, as it can directly convert NH4+ to N2 and H2 in one step when the electrode is arranged as an electron acceptor. High-value-added hydrogen can potentially be recovered with efficient nitrogen removal using this concept, maximizing the benefits of BENR. Using alternative electron acceptors, such as electrodes and metal ions, for complete total nitrogen removal is a promising technology to substitute NO2- production from NH4+ oxidation by aeration. However, the requirement of electron donors for NO3- reduction, low NH4+ removal efficiency, and low competitiveness of exoelectrogenic bacteria still remain the main obstacles. The future direction for successful BENR should aim to achieve complete anaerobic NH4+ oxidation without any electron acceptor and to maximize selectivity in H2 production. Therefore, the bioelectrochemical pathways and balances between efficient nitrogen removal and high-value-added chemical production should be further studied for carbon and energy neutralities.


Subject(s)
Ammonium Compounds , Denitrification , Nitrogen/metabolism , Bioreactors/microbiology , Anaerobiosis , Oxidation-Reduction , Oxidants , Carbon , Ammonium Compounds/metabolism , Sewage/microbiology
3.
Vet Med Sci ; 8(2): 445-449, 2022 03.
Article in English | MEDLINE | ID: mdl-35132803

ABSTRACT

OBJECTIVE: The aim of this report is to document the case of a dog that developed pleural effusion as a potential side-effect to the administration of a high-dose of amlodipine. CASE SUMMARY: A Yorkshire terrier dog (13-year-old, castrated male, 4.5 kg) presented with severe systemic hypertension (>200 mmHg), hyperkalaemia, and acute pancreatitis. The dog had hyperadrenocorticism, chronic valvular heart disease, chronic kidney disease, and cerebellar infarction as underlying diseases. Additionally, the dog had laboured breathing and tachypnoea during hospitalization. Screening examinations revealed a pleural effusion (pure transudate) for which hypoalbuminemia and thromboembolism were ruled out as the causes. Therefore, the adverse drug event of an anti-hypertensive drug (amlodipine) was tentatively diagnosed. CONCLUSIONS: Pleural effusion resolved within 24 h of reducing the dosage of amlodipine. Hence, the dog was diagnosed with amlodipine-induced pleural effusion. Rarely, amlodipine can cause pleural effusion after high-dose administrations in humans, but only two cases of peripheral edema have been reported in animals. If pleural effusion occurs in hypertensive patients administered amlodipine, it should be considered as the potential cause.


Subject(s)
Dog Diseases , Hypertension , Pancreatitis , Pleural Effusion , Acute Disease , Amlodipine/adverse effects , Animals , Dog Diseases/chemically induced , Dog Diseases/drug therapy , Dogs , Exudates and Transudates , Humans , Hypertension/chemically induced , Hypertension/drug therapy , Hypertension/veterinary , Male , Pancreatitis/complications , Pancreatitis/veterinary , Pleural Effusion/chemically induced , Pleural Effusion/veterinary
4.
PLoS One ; 16(11): e0256651, 2021.
Article in English | MEDLINE | ID: mdl-34807933

ABSTRACT

BACKGROUND: Preconditioning with lipopolysaccharide (LPS) is used to improve the secretion of anti-inflammatory agents in B cells. However, there are only a few studies on canine B cells. OBJECTIVE: This study aimed to evaluate the immune regulatory capacity of canine peripheral blood mononuclear cell-derived B cells pretreated with LPS. METHODS: Canine B cells were isolated from canine peripheral blood mononuclear cells, which were obtained from three healthy canine donors. The B cells were preconditioned with LPS, and then cell viability and the expression of the regulatory B cell marker were assessed. Finally, RNA extraction and immunofluorescence analysis were performed. RESULTS: LPS primed B cells expressed the interleukin (IL)-10 surface marker and immunoregulatory gene expression, such as IL-10, programmed death-ligand 1, and transforming growth factor beta. Macrophages in the inflammatory condition cocultured with primed B cells were found to have significantly down-regulated pro-inflammatory cytokine, such as tumor necrosis factor-α, and up-regulated anti-inflammatory cytokines such as IL-10. Additionally, it was revealed that co-culture with primed B cells re-polarized M1 macrophages to M2 macrophages. CONCLUSIONS: This study revealed that LPS-primed B cells have an anti-inflammatory effect and can re-polarize macrophages, suggesting the possibility of using LPS-primed B cells as a therapeutic agent for its anti-inflammatory effects and immune modulation.


Subject(s)
B-Lymphocytes/drug effects , Cell Polarity/drug effects , Immunomodulation/drug effects , Leukocytes, Mononuclear/drug effects , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Animals , B-Lymphocytes/cytology , Dogs , Leukocytes, Mononuclear/cytology , Macrophage Activation/drug effects , Macrophages/cytology
5.
AERA Open ; 5(3): 1-22, 2019.
Article in English | MEDLINE | ID: mdl-32832579

ABSTRACT

Socioeconomic achievement gaps have long been a central focus of educational research. However, not much is known about how (and why) between-district gaps vary among states, even though states are a primary organizational level in the decentralized education system in the United States. Using data from the Stanford Education Data Archive (SEDA), this study describes state-level socioeconomic achievement gradients and the growth of these gradients from Grades 3 to 8. We also examine state-level correlates of the gradients and their growth, including school system funding equity, preschool enrollment patterns, the distribution of teachers, income inequality, and segregation. We find that socioeconomic gradients and their growth rates vary considerably among states, and that between-district income segregation is positively associated with the socioeconomic achievement gradient.

6.
J Adv Prosthodont ; 3(4): 204-15, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22259704

ABSTRACT

PURPOSE: The aim of this retrospective study is to analyze the relationship between local factors and survival rate of dental implant which had been installed and restored in Seoul Veterans Hospital dental center for past 10 years. And when the relationship is found out, it could be helpful to predict the prognosis of dental implants. MATERIALS AND METHODS: A retrospective study of patients receiving root-shaped screw-type dental implants placed from January 2000 to December 2009 was conducted. 6385 implants were placed in 3755 patients. The following data were collected from the dental records and radiographs: patient's age, gender, implant type and surface, length, diameter, location of implant placement, bone quality, prosthesis type. The correlations between these data and survival rate were analyzed. Statistical analysis was performed with the use of Kaplan-Meier analysis, Chi-square test and odds ratio. RESULTS: In all, 6385 implants were placed in 3755 patients (3120 male, 635 female; mean age 65 ± 10.58 years). 108 implants failed and the cumulative survival rate was 96.33%. There were significant differences in age, implant type and surface, length, location and prosthesis type (P<.05). No significant differences were found in relation to the following factors: gender, diameter and bone quality (P>.05). CONCLUSION: Related factors such as age, implant type, length, location and prosthesis type had a significant effect on the implant survival.

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