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1.
J Colloid Interface Sci ; 666: 540-546, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613976

RESUMO

Na3V2(PO4)3 is considered as one of the most promising cathodes for sodium ion batteries owing to its fast Na+ diffusion, good structural stability and high working potential. However, its practical application is limited by its low intrinsic electronic conductivity. Herein, a carbon coated Cu2+-doped Na3V2(PO4)3 cathode was prepared. The carbon coating not only improve its apparent conductivity, but also inhibit crystal growth and prevent agglomeration of particles. Moreover, Cu2+ doping contributes to an enhanced intrinsic conductivity and decreased Na+ diffusion energy barrier, remarkably boosting its charge transfer kinetics. Based on the structure characterizations, electrochemical performances tests, charge transfer kinetics analyses and theoretical calculations, it's proved that such an elaborate design ensures the excellent rate performances (116.9 mA h g-1 at 0.1C; 92.6 mA h g-1 at 10C) and distinguished cycling lifespan (95.8 % retention after 300 cycles at 1C; 84.8 % retention after 3300 cycles at 10C). Besides, a two-phase reaction mechanism is also confirmed via in-situ XRD. This research is expected to promote the development of Na3V2(PO4)3-based sodium ion batteries with high energy/power density and excellent cycling lifespan.

2.
J Hazard Mater ; 469: 133940, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38457979

RESUMO

Glutaraldehyde-Didecyldimethylammonium bromides (GDs) has been frequently and widely employed in livestock and poultry breeding farms to avoid epidemics such as African swine fever, but its long-term effect on the active sludge microorganisms of the receiving wastewater treatment plant was keep unclear. Four simulation systems were built here to explore the performance of aerobic activated sludge with the long-term exposure of GDs and its mechanism by analyzing water qualities, resistance genes, extracellular polymeric substances and microbial community structure. The results showed that the removal rates of CODCr and ammonia nitrogen decreased with the exposure concentration of GDs increasing. It is worth noting that long-term exposure to GDs can induce the horizontal transfer and coordinated expression of a large number of resistance genes, such as qacE, sul1, tetx, and int1, in drug-resistant microorganisms. Additionally, it promotes the secretion of more extracellular proteins, including arginine, forming a "barrier-like" protection. Therefore, long-term exposure to disinfectants can alter the treatment capacity of activated sludge receiving systems, and the abundance of resistance genes generated through horizontal transfer and coordinated expression by drug-resistant microorganisms does pose a significant threat to ecosystems and health. It is recommended to develop effective pretreatment methods to eliminate disinfectants.


Assuntos
Febre Suína Africana , Desinfetantes , Animais , Suínos , Esgotos/química , Matriz Extracelular de Substâncias Poliméricas , Eliminação de Resíduos Líquidos/métodos , Desinfetantes/toxicidade , Ecossistema
3.
Water Res ; 253: 120141, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377919

RESUMO

Anaerobic ammonium oxidation (ANAMMOX)-mediated system is a cost-effective green nitrogen removal process. However, there are few examples of successful application of this advanced wastewater denitrification process in wastewater treatment plants, and the understanding of how to implement anaerobic ammonia oxidation process in full-scale is still limited. In this study, it was found that the abundance of anaerobic ammonia-oxidizing bacteria (AnAOB) in the two livestock wastewater plants named J1 and J2, respectively, showed diametrically opposed trends of waxing and waning with time. The microbial communities of the activated sludge in the two plants at different time were sampled and analyzed by high-throughput sequencing of 16S rRNA genes. Structural equation models (SEMs) were used to reveal the key factors affecting the realization of the ANAMMOX. Changes in the concentration of dissolved oxygen and C/N had a significant effect on the relative abundance of anaerobic ammonia oxidation bacteria (AnAOB). The low concentration of DO (0.2∼0.5 mg/L) could inhibit the activity of nitrifying bacteria (NOB) to achieve partial oxidation of ammonia nitrogen and provide sufficient substrate for the growth of AnAOB, similar to the CANON (Completely Autotrophic Nitrogen removal Over Nitrite). Unlike CANON, heterotrophic denitrification is also a particularly critical part of the livestock wastewater treatment, and a suitable C/N of about 0.6 could reduce the competition risk of heterotrophic microorganisms to AnAOB and ensure a good ecological niche for AnAOB. Based on the results of 16S rRNA and microbial co-occurrence networks, it was discovered that microorganisms in the sludge not only had a richer network interaction, but also achieved a mutually beneficial symbiotic interaction network among denitrifying bacteria (Pseudomonas sp., Terrimonas sp., Dokdonella sp.), AnAOB (Candidatus Brocadia sp.) at DO of 0.2∼0.5 mg/L and C/N of 0.6. Among the top 20 in abundance of genus level, AnAOB had a high relative abundance of 27.66%, followed by denitrifying bacteria of 3.67%, AOB of 0.64% and NOB of 0.26%, which is an essential indicator for the emergence of an AnAOB-dominated nitrogen removal cycle. In conclusion, this study highlights the importance of dissolved oxygen and C/N regulation by analyzing the mechanism of ANAMMOX sludge extinction and growth in two plants under anthropogenic regulation of AnAOB in full-scale wastewater treatment systems.


Assuntos
Águas Residuárias , Purificação da Água , Animais , Esgotos , Amônia , Gado , Oxidação Anaeróbia da Amônia , RNA Ribossômico 16S , Reatores Biológicos/microbiologia , Bactérias/genética , Agricultura , Nitrogênio , Oxigênio , Oxirredução , Desnitrificação
4.
Braz J Microbiol ; 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38340257

RESUMO

Multiple copper oxidase (MCO) like laccase is widely distributed in higher plant, fungi and bacteria. This study identified MCO like laccase producing bacterium isolated from a wastewater treatment plant based on 16S rRNA sequence analysis, and they were further confirmed by phylogenetic reconstruction. Biochemical and gene characterization of MCO like laccase from Stenotrophomonas sp. YBX1 is presented. Purification of MCO like laccase was carried out by ion exchange HQ Trap column and followed by gel filtration spheracryl S-100 column. The purified MCO like laccase from Stenotrophomonas sp. YBX1 shows a total activity of 1252 units and specific activity 391.2 U/mg and protein concentration 0.32 mg/mL. In SDS PAGE, the approximate molecular mass was found at 66 kDa and further confirmed from an MS spectrum of MALDI-TOF. The purified MCO like laccase is capable of degradation of antibiotics such as tetracycline completely, whereas oxytetracycline (78%) and ampicillin (62%) degraded within 96 min without any redox mediators at pH 5 and 30 ºC. Its degradation pathway was based on identification of metabolites by LC-MS spectrum. The enzymatic degradation may be used in advanced treatment of antibiotics containing wastewater.

5.
Medicine (Baltimore) ; 103(7): e36954, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363897

RESUMO

BACKGROUND: Intestinal nontuberculous mycobacteriosis due to nontuberculous mycobacteria infection has clinical manifestations similar to intestinal tuberculosis and inflammatory bowel disease, causing difficulties in clinical diagnosis. CASE PRESENTATION: A 42-year-old male patient was admitted to the Sino-Japanese Friendship Hospital of Jilin University in June 2021 for diarrhea and intermittent hematochezia since April 2021. He was diagnosed with inflammatory intestinal disease by colonoscopy and midtransverse colon biopsy. However, the symptoms did not relieve after 2 months of mesalazine treatment. In August 2021, the patient was admitted to the outpatient department for suspected "intestinal tuberculosis." A diagnosis of intestinal nontuberculous mycobacteriosis was confirmed based on pathology and nucleotide-based matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). After 2 weeks of antimycobacterial therapy, the patient's diarrhea was relieved, and hematochezia no longer appeared. In November 2021, recolonoscopy revealed scattered erosions and ulcers in ileocecal valve and ascending colon, while both nucleotide-based MALDI-TOF MS and next-generation sequencing could still detect Mycobacterium intracellulare. CONCLUSION: This study reported a patient with an intestinal nontuberculous mycobacteriosis diagnosed by colonoscopy biopsy and nucleotide-based MALDI-TOF MS, and symptoms were relieved after antimycobacterial treatment.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Tuberculose dos Linfonodos , Masculino , Humanos , Adulto , Micobactérias não Tuberculosas , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Diarreia , Hemorragia Gastrointestinal , Nucleotídeos
6.
J Hazard Mater ; 466: 133599, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38280323

RESUMO

The intestinal microbiome might be both a sink and source of resistance genes (RGs). To investigate the impact of environmental stress on the disturbance of exogenous multidrug-resistant bacteria (mARB) within the indigenous microbiome and proliferation of RGs, an intestinal conjugative system was established to simulate the invasion of mARB into the intestinal microbiota in vitro. Oxytetracycline (OTC) and heavy metals (Zn, Cu, Pb), commonly encountered in aquaculture, were selected as typical stresses for investigation. Adenosine 5'-triphosphate (ATP), hydroxyl radical (OH·-) and extracellular polymeric substance (EPS) were measured to investigate their influence on the acceptance of RGs by intestinal bacteria. The results showed that the transfer and diffusion of RGs under typical combined stressors were greater than those under a single stressor. Combined effect of OTC and heavy metals (Zn, Cu) significantly increased the activity and extracellular EPS content of bacteria in the intestinal conjugative system, increasing intI3 and RG abundance. OTC induced a notable inhibitory response in Citrobacter and exerted the proportion of Citrobacter and Carnobacterium in microbiota. The introduction of stressors stimulates the proliferation and dissemination of RGs within the intestinal environment. These results enhance our comprehension of the typical stresses effect on the RGs dispersal in the intestine.


Assuntos
Metais Pesados , Oxitetraciclina , Animais , Antibacterianos/farmacologia , Xenopus laevis , Matriz Extracelular de Substâncias Poliméricas , Oxitetraciclina/farmacologia , Bactérias/genética , Metais Pesados/toxicidade , Intestinos
7.
Small ; : e2308716, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072769

RESUMO

The selective quantification of copper ions (Cu2+ ) in biosamples holds great importance for disease diagnosis, treatment, and prognosis since the Cu2+ level is closely associated with the physiological state of the human body. While it remains a long-term challenge due to the extremely low level of free Cu2+ and the potential interference by the complex matrices. Here, a pore-engineered hydrogen-bonded organic framework (HOF) fluorosensor is constructed enabling the ultrasensitive and highly selective detection of free Cu2+ . Attributing to atomically precise functionalization of active amino "arm" within the HOF pores and the periodic π-conjugated skeleton, this porous HOF fluorosensor affords high affinity toward Cu2+ through double copper-nitrogen (Cu─N) coordination interactions, resulting in specific fluorescence quenching of the HOF as compared with a series of substances ranging from other metal ions, metabolites, amino acids to proteins. Such superior fluorescence quenching effect endows the Cu2+ quantification by this new HOF sensor with a wide linearity of 50-20 000 nm, a low detection limit of 10 nm, and good recoveries (89.5%-115%) in human serum matrices, outperforming most of the reported approaches. This work highlights the practicability of hydrogen-bonded supramolecular engineering for designing facile and ultrasensitive biosensors for clinical free Cu2+ determination.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37971448

RESUMO

Objective: To analyze the clinical effect of rehabilitation new fluid combined with Sanjie analgesic capsules in the treatment of granulomatous lobular mastitis (GLM) and thyroiditis and the impact on immune indexes of patients. Methods: For a retrospective study, we selected 150 patients with GLM and 150 patients with thyroiditis admitted to The Fourth Hospital of Shijiazhuang from January 2021 to January 2022. We divided them into three groups based on the treatment methods. Control group 1 (CG1) included patients treated with rehabilitation new fluid alone, while control group 2 (CG2) included patients treated with the Sanjie analgesic capsules alone. The third group, the observation group (OG), included patients treated with rehabilitation new fluid (extract of drying body from Periplaneta americana) at an oral dose of 10 ml combined with Sanjie analgesic capsules. There were 50 patients in each group. The clinical efficacy, symptom improvement, the level changes of free triiodothyronine (FT3), free tetraiodothyronine (FT4), and thyroid stimulating hormone (TSH), and the changes of immune indexes such as CD4+ (cluster of differentiation 4+), CD25+ (cluster of differentiation 25+), CD68+ (cluster of differentiation 68+) and CD138+ (cluster of differentiation 138+) were analyzed. Results: After treatment, the total treatment effectiveness of GLM in the OG was 94%, which was significantly higher than 80% in the CG1 and 78% in the CG2 (P = .037, .021), while the total treatment effectiveness of thyroiditis in the OG was 92%, which was significantly higher than 76% in the CG1 and 74% in the CG2 (P = .029, 0.017). The scores of breast pain, breast overflow, tumor size, local skin changes, and axillary fossa lymphadenectasis of the affected side in the OG of GLM were better than those in CG1 (Pbreast pain < .001, 95%CI: 0.573-1.747; Pbreast overflow = .022, 95%CI: 0.074-0.905; Ptumor size = .008, 95%CI: 0.231-1.489; Plocal skin changes = .001, 95%CI: 0.382-1.498; Paxillary fossa lymphadenectasis of the affected side = .011, 95%CI: 0.096-0.704) and CG2 (Pbreast pain = .001, 95%CI: 0.449-1.711; Pbreast overflow = .049, 95%CI: 0.002-0.798; Ptumor size =0.019, 95%CI: 0.132-1.428; Plocal skin changes < .001, 95%CI: 0.563-1.517; Paxillary fossa lymphadenectasis of the affected side = .001, 95%CI: 0.202-0.678). The levels of FT3 and FT4 in the OG of thyroiditis were higher than CG1 (PFT3 < .001, 95%CI: 0.951-1.590; PFT4 < .001, 95%CI: 1.421-2.618) and CG2 (PFT3 < .001, 95%CI: 0.943-1.643; PFT4 < .001, 95%CI: 1.521-2.758), and the TSH level was lower compared with CG1 (PTSH < .001, 95%CI: 2.409-3.070) and CG2 (PTSH < .001, 95%CI: 2.540-3.230). The immune indexes of GLM were improved, and the levels of CD4+, CD25+, CD68+, and CD138+ in the OG were better than those in the CG1 (PCD4+ < .001, 95%CI: 2.967-4.912; PCD25+ < .001, 95%CI: 3.707-5.212; PCD68+ < .001, 95%CI: 1.445-2.200; PCD138+ < .001, 95%CI: 3.922-5.510) and CG2 (PCD4+ < .001, 95%CI: 3.093-4.995; PCD25+ < .001, 95%CI: 3.527-4.904; PCD68+ < .001, 95%CI: 1.334-2.216; PCD138+ < .001, 95%CI: 3.878-5.352). The immune indexes of thyroiditis were improved, and the levels of CD4+, CD25+, CD68+, and CD138+ in the OG were better than those in the CG1 (PCD4+ < .001, 95%CI: 4.235-6.117; PCD25+ < .001, 95%CI: 3.300-4.810; PCD68+ < .001, 95%CI: 1.173-1.939; PCD138+ < .001, 95%CI: 3.704-4.881) and CG2 (PCD4+ < .001, 95%CI: 3.136-5.422; PCD25+ < .001, 95%CI: 3.182-4.615; PCD68+ < .001, 95%CI: 1.216-2.113; PCD138+ < .001, 95%CI: 4.145-5.527). Conclusion: The clinical effect of rehabilitation new fluid combined with Sanjie analgesic capsule in the treatment of GLM and thyroiditis is remarkable, which enables enhancement of the treatment efficiency, and improves patients' clinical symptoms, functional indexes, and the levels of immune indexes, as a direction for the follow-up treatment in the clinic.

9.
Mol Biotechnol ; 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37817028

RESUMO

N6-methyladenosine (m6A) functions as an important regulator in various human cancers, including gastric cancer. The immunotherapy targeting PD-1/PD-L1 has brought hope for advanced gastric cancer therapeutic. Here, present research aims to investigate the roles of m6A reader IGF2BP1 on gastric cancer tumor development and immune escape. Results indicated that IGF2BP1 up-regulated in the gastric cancer tissue and correlated with poor prognosis of gastric cancer patients. IGF2BP1 overexpression augmented the proliferation of co-cultured gastric cancer cells, and mitigated the CD8+ T cells mediated anti-tumor response, including IFN-γ secretion, surface PD-L1 level, and cytotoxicity of CD8+ T cells. Meanwhile, IGF2BP1 silencing exerted the opposite effects. In silico analysis revealed that there was a remarkable m6A modified site on PD-L1 mRNA. Moreover, the IGF2BP1 overexpression enhanced the stability of PD-L1 mRNA, thereby deteriorating the immune escape of gastric cancer cells. Collectively, these results describe a novel regulatory mechanism of IGF2BP1 by regulating PD-L1 through m6A epigenetic modification, which might provide insights for gastric cancer immunotherapies.

10.
Sci Total Environ ; 905: 167040, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37709083

RESUMO

The abuse and overuse of antibiotics increased not only the exposure of aquatic animals to antibiotics but also the development of resistance in pathogenic bacteria. To investigate the effects and mechanisms of exposure, a long-term experiment lasting 120 days was conducted in which Xenopus tropicalis was exposed to single and combined stress factors of multiresistant pathogenic Shigella flexneri and ciprofloxacin (CIP). The intestinal oxidative stress, immune factors and flora, as well as the brain-gut axis correlation factors of X. tropicalis, were tracked to account for the response of aquatic animals to the exogenous pollutants. SOD activity and MDA content were significantly increased in stressed X. tropicalis (p < 0.001), while the levels of proinflammatory factors (IL-1ß, IFN-γ) were significantly reduced (p < 0.01). The content of intestinal beneficial bacteria decreased and that of harmful bacteria increased in the intestinal flora of the stressed X. tropicalis (p < 0.001). These results suggested that S. flexneri and CIP disturbed the intestinal flora and caused oxidative damage in the host, and the body produced a series of responses, such as oxidative stress responses and regulation of the expression of immune factors, to maintain the balance of antioxidant inflammation. Significant changes in the expression of intestinal neurotransmitters (5-HT, CGRP) and brain peptides (BDNF, NCAM, NPY) (p < 0.05) also indicated that the brain-gut axis interaction was disrupted. In addition, although the coexisting CIP could reduce intestinal toxicity caused by S. flexneri, the amount of intestinal pathogenic bacteria Desulfovibrio increased significantly. Moreover, compared with the single exposure group, SOD activity, CAT activity and MDA content were significantly reduced in the dual exposure group. Therefore, the health risks of multiresistant pathogenic bacteria on the intestinal and brain-gut axis interaction should be given more attention, and the interaction of brain-gut axis is more important when antibiotics coexist.


Assuntos
Ciprofloxacina , Shigella flexneri , Animais , Ciprofloxacina/toxicidade , Antibacterianos/toxicidade , Bactérias , Fatores Imunológicos , Superóxido Dismutase
11.
ISME J ; 17(11): 2003-2013, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37700035

RESUMO

Horizontal gene transfer (HGT) has been considered the most important pathway to introduce antibiotic resistance genes (ARGs), which seriously threatens human health and biological security. The presence of ARGs in the aquatic environment and their effect on the intestinal micro-ecosystem of aquatic animals can occur easily. To investigate the HGT potential and rule of exogenous ARGs in the intestinal flora, a visual conjugative model was developed, including the donor of dual-fluorescent bacterium and the recipient of Xenopus tropicalis intestinal microbiome. Some common pollutants of oxytetracycline (OTC) and three heavy metals (Zn, Cu and Pb) were selected as the stressor. The multi-techniques of flow cytometry (FCM), scanning electron microscopy (SEM), atomic force microscopy (AFM), single-cell Raman spectroscopy with sorting (SCRSS) and indicator analysis were used in this study. The results showed that ARG transfer could occur more easily under stressors. Moreover, the conjugation efficiency mainly depended on the viability of the intestinal bacteria. The mechanisms of OTC and heavy metal stressing conjugation included the upregulation of ompC, traJ, traG and the downregulation of korA gene. Moreover, the enzymatic activities of SOD, CAT, GSH-PX increased and the bacterial surface appearance also changed. The predominant recipient was identified as Citrobacter freundi by SCRSS, in which the abundance and quantity of ARG after conjugation were higher than those before. Therefore, since the diversity of potential recipients in the intestine are very high, the migration of invasive ARGs in the microbiome should be given more attention to prevent its potential risks to public health.


Assuntos
Microbioma Gastrointestinal , Metais Pesados , Microbiota , Oxitetraciclina , Animais , Humanos , Oxitetraciclina/farmacologia , Genes Bacterianos , Metais Pesados/toxicidade , Antibacterianos/farmacologia , Bactérias/genética , Plasmídeos/genética , Transferência Genética Horizontal
12.
Artigo em Inglês | IBECS | ID: ibc-222292

RESUMO

Background: This study aims to propose a lateral cervical stria approach for selective neck dissection (SND) in patients of early-stage oral malignancies. Material and methods: The lateral cervical stria approach was used in 11 patients undergoing SND between December 2020 and March 2022. The surgical incision was located in submandibular cervical stria, with a length of 5.0 cm. The ipsilateral SND was performed according to the pathological type, covering part or all of I-V levels. Perioperative variables including operation time, blood loss, drainage volume, number of lymph node as well as complications were assessed. The score of appearance using the University of Washington Quality of Life Questionnaire (UW-QOL) was recorded 6-month postoperatively. Results: Direct closure of primary lesion was performed in ten patients and a forearm free flap reconstruction was used in one patient. No wound breakdown or infection was found in all cases. The mean operative time of SND was 157.63±27.39 min. The volume of intraoperative blood loss and postoperative drainage was 120.45±36.77 ml and 314.09±98.82 ml, respectively. The mean number of retrieved lymph nodes was 17.89±6.03 (ranging from 12 to 31). Postoperative complications included mild static lower lip deviation (n=1), shoulder discomfort (n=1) and mild auricular paraesthesia (n=1). The mean score of appearance was 86.36±13.06, with 100 scores in 5 patients and 75 scores in 6 patients. Conclusions: The lateral cervical stria approach for SND in early-stage oral malignancies is reliable, achieving to satisfactory functional and aesthetic outcomes. (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Neoplasias Bucais , Estética , Esvaziamento Cervical , China
13.
Materials (Basel) ; 16(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36984032

RESUMO

The welding titanium cathode roller has the obvious advantages of low cost, high efficiency, and no diameter restriction. Unfortunately, the longitudinal weld on the cathode roller adversely impacts the quality of the electrolytic copper foil due to the great difference between the microstructure of the weld zone and the base metal. Thus, it is crucial to reduce their difference by regulating the microstructure of the weld zone. In this study, a novel complex treatment of heat treatment and sandblasting is primarily developed for regulating the microstructure of the weld zone. The results show that the novel complex treatment has an efficient effect on regulating the microstructure of the weld zone and making the microstructure in the weld zone close to that of the base metal. During vacuum annealing, the microstructure of the weld zone is refined to some degree, and 650 °C annealing has the optimal effect, which can effectively reduce the ratio of α phase's length to width and reduce the microstructure difference between the weld zone and the base metal. At the same time, with an increase in the annealing temperature, the tensile strength and yield strength decreased by about 10 MPa; the elongation after fracture increased by 20%; the average microhardness of the WZ and the HAZ decreased by about 10 HV0.10; and that of the BM decreased by about 3 HV0.10. The heat treatment after welding can effectively adjust the properties of the weld zone, reduce the hardness and strength, and improve the toughness. The subsequent sandblasting after annealing can further refine the grain size in the weld zone and make the microstructure in the weld zone close to that of the base metal. Sandblasting after annealing can further refine the grain in the weld zone and make the microstructure in the weld zone close to that of base metal. Meanwhile, an application test confirmed that the adverse impact of a longitudinal weld on the quality of electrolytic copper foil could be resolved by adopting this novel complex treatment. Therefore, this study provides valuable technical support for the "welding" manufacturing of the titanium sleeves of the cathode roller.

14.
Water Res ; 235: 119799, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36965294

RESUMO

Microbial-driven nitrogen removal is a crucial step in modern full-scale wastewater treatment plants (WWTPs), and the complexity of nitrogen transformation is integral to the various wastewater treatment processes. A full understanding of the overall nitrogen cycling networks in WWTPs is therefore a prerequisite for the further enhancement and optimization of wastewater treatment processes. In this study, metagenomics and metatranscriptomics were used to elucidate the microbial nitrogen removal processes in an ammonium-enriched full-scale WWTP, which was configured as an anaerobic-anoxic-anaerobic-oxic system for efficient nitrogen removal (99.63%) on a duck breeding farm. A typical simultaneous nitrification-anammox-denitrification (SNAD) process was established in each tank of this WWTP. Ammonia was oxidized by ammonia-oxidizing bacteria (AOB), archaea (AOA), and nitrite-oxidizing bacteria (NOB), and the produced nitrite and nitrate were further reduced to dinitrogen gas (N2) by anammox and denitrifying bacteria. Visible red anammox biofilms were formed successfully on the sponge carriers submerged in the anoxic tank, and the nitrogen removal rate by anammox reaction was 4.85 times higher than that by denitrification based on 15N isotope labeling and analysis. This supports the significant accumulation of anammox bacteria on the carriers responsible for efficient nitrogen removal. Two distinct anammox bacteria, named "Ca. Brocadia sp. PF01" and "Ca. Jettenia sp. PF02", were identified from the biofilm in this investigation. By recovering their genomic features and their metabolic capabilities, our results indicate that the highly active core anammox process found in PF01, suggests extending its niche within the plant. With the possible contribution of the dissimilatory nitrate reduction to ammonium (DNRA) reaction, enriching PF02 within the biofilm may also be warranted. Collectively, this study highlights the effective design strategies of a full-scale WWTP with enrichment of anammox bacteria on the carrier materials for nitrogen removal and therefore the biochemical reaction mechanisms of the contributing members.


Assuntos
Compostos de Amônio , Purificação da Água , Amônia/metabolismo , Desnitrificação , Águas Residuárias , Nitritos/metabolismo , Nitratos/metabolismo , Oxidação Anaeróbia da Amônia , Nitrogênio/metabolismo , Anaerobiose , Oxirredução , Reatores Biológicos/microbiologia , Compostos de Amônio/metabolismo , Bactérias/genética , Bactérias/metabolismo , Purificação da Água/métodos
15.
Nanomaterials (Basel) ; 13(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36616124

RESUMO

Bi2MoO6 was one of the important bismuth-based semiconductors with a narrow bandgap, and has been widely used in selective oxidation catalysts, supercapacitors, and energy-storage devices. A series of Bi2MoO6/ZnO composite photocatalysts with different mass ratios were synthesized by the hydrothermal method. The synthesized samples were characterized by XRD, PL, UV-Vis, SEM, TEM, XPS, and BET analysis techniques. Under visible light conditions, Methylene blue (MB) was used as the target degradation product to evaluate its photocatalytic performance. The results showed that the degradation rate constant of Bi2MoO6/ZnO (0.4-BZO) was about twice that of the traditional photocatalysis of ZnO. The Bi2MoO6/ZnO composite catalyst maintained stable performance after four consecutive runs. The high photocatalytic activity of Bi2MoO6/ZnO was attributed to the efficient electron transport of the heterojunction, which accelerates the separation of electron-hole pairs and reduces the probability of carrier recombination near the Bi2MoO6/ZnO heterojunction. Bi2MoO6/ZnO nanocomposites have potential applications in the field of photodegradation.

16.
J Environ Manage ; 325(Pt A): 116520, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306650

RESUMO

The performance of a mixotrophic photoelectroactive biofilm reactor (MPBR) was improved in order to achieve enhanced simultaneous removal of multiple aqueous pollutants and the production of valuable biomass. The MPBR was optimized by integrating the regulation of light intensity (3000, 8000 and 23000 lux) and microbial extracellular electron extraction (using an electrode at -0.3, 0 and 0.3 V). Results showed that the MPBR operated at a high light intensity (23000 lux) with a potential of -0.3 V (Coulomb efficiency (CE) of 9.65%) achieved maximum pollutant removal efficiencies, effectively removing 65% NH4+-N, 95% PO43--P and 52% sulfadiazine (SDZ) within 72 h, exhibiting an increase by 30%, 56% and 26% compared to an MPBR operated at the same light intensity but without an externally applied potential. The use of an electrode with an applied potential of -0.3V was most suitable for the extraction of photosynthetic electrons from the photoelectroactive biofilm, in which Rhodocyclaceae was highly enriched, effectively alleviating photoinhibition and thereby enhancing N, P assimilation and SDZ degradation under high light conditions. A maximum lipid content of 409.28 mg/g was obtained under low light intensity (3000 lux) conditions with an applied potential of 0.3 V (CE 9.08%), while a maximum protein content of 362.29 mg/g was obtained at a low light intensity (3000 lux) and 0 V (CE 10.71%). The selective enrichment of Chlorobium and the subsequent enhanced conversion of excess available carbon under low light and positive potential stimulation conditions, were responsible for the enhanced accumulation of proteins and lipids in biomass.


Assuntos
Antibacterianos , Elétrons , Biofilmes , Biomassa , Nutrientes , Sulfadiazina , Águas Residuárias , Reatores Biológicos
17.
J Environ Sci (China) ; 127: 431-440, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522075

RESUMO

Direct discharge of aquaculture wastewater may have toxic effects, due to the presence of heavy metals, antibiotics, and even resistant pathogens, but little attention has been given. Here, tanks simulating a wild ecosystem were built to study the effects of long-term exposure to duck wastewater containing oxytetracycline (OTC) and/or arsenic (As) on the growth, physiological function, and gut microbiota evolution of Xenopus tropicalis. The results showed that duck wastewater had no apparent impact on X. tropicalis, but the impact increased significantly (P < 0.05) with exposure to OTC and/or As, especially the impact on body weight and growth rate. Biochemical indicators revealed varying degrees of oxidative stress damage, hepatotoxicity (inflammation, necrosis, and sinusoids), and collagen fibrosis of X. tropicalis in all treated groups after 72 days of exposure, which indirectly inhibited X. tropicalis growth. Moreover, 16S rDNA amplicon sequencing results showed that the gut microbiota structure and metabolic function were perturbed after chronic exposure, which might be the leading cause of growth inhibition. Interestingly, the abundance of intestinal resistance genes (RGs) increased with exposure time owing to the combined direct and indirect effects of stress factors in duck wastewater. Moreover, once the RGs were expressed, the resistance persisted for at least 24 days, especially that conferred by tetA. These results provide evidence of the toxic effects of DW containing OTC (0.1-4.0 mg/L) and/or As (0.3-3.5 µg/L) on amphibians and indicate that it is vital to limit the usage of heavy metals and antibiotics on farms to control the biotoxicity of wastewater.


Assuntos
Arsênio , Oxitetraciclina , Animais , Oxitetraciclina/toxicidade , Águas Residuárias , Patos , Arsênio/toxicidade , Xenopus , Ecossistema , Antibacterianos/toxicidade
18.
Environ Pollut ; 316(Pt 1): 120551, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332708

RESUMO

Multidrug-resistant bacteria, especially pathogens, pose a serious threat to disease treatment and recovery, but their potential toxicity to animal development is not entirely clear. As the most important site for nutrient absorption, we studied the intestinal microbiome of Xenopus tropicalis by analyzing the effect of multidrug-resistant Shigella on its intestinal health. Unlike in the control, Shigella intake promoted the secretion of neutral mucus and inhibited intestinal development and weight gain. Following 60 days of exposure, intestinal crypt atrophy, intestinal villus shortening, internal cavity enlargement, and external mucosal muscle disintegration were observed. The circular and longitudinal intestinal muscles became thinner with increasing pathogen exposure. In addition, the presence of Shigella altered the expression of multiple cytokines and classic antioxidant enzyme activities in the gut, which may have caused the intestinal lesions that we observed. 16 S rDNA sequencing analysis of intestinal samples showed that exposure to Shigella destroyed the normal gut microbial abundance and diversity and increased the functional bacterial ratio. Notably, the increased abundance of intestinal antibiotic resistance genes (ARGs) may imply that the resistance genes carried by Shigella easily migrate and transmit within the intestine. Our results expand existing knowledge concerning multidrug-resistant Shigella-induced intestinal toxicity in X. tropicalis and provide new insights for the threat assessment of resistance genes carried by drug-resistant pathogens.


Assuntos
Poluentes Ambientais , Microbioma Gastrointestinal , Shigella , Animais , Poluentes Ambientais/farmacologia , Shigella/genética , Farmacorresistência Bacteriana Múltipla , Antibacterianos/farmacologia
19.
Molecules ; 29(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38202816

RESUMO

Heterostructured materials show great potential to enhance the specific capacity, rate performance and cycling lifespan of lithium-ion batteries owing to their unique interfaces, robust architectures, and synergistic effects. Herein, a polypyrrole (PPy)-coated nanotube-like Mo3S4/CoMo2S4 heterostructure is prepared by the hydrothermal and subsequent in situ polymerization methods. The well-designed nanotube-like structure is beneficial to relieve the serious volume changes and facilitate the infiltration of electrolytes during the charge/discharge process. The Mo3S4/CoMo2S4 heterostructure could effectively enhance the electrical conductivity and Li+ transport kinetics owing to the refined energy band structure and the internal electric field at the heterostructure interface. Moreover, the conductive PPy-coated layer could inhibit the obvious volume expansion like a firm armor and further avoid the pulverization of the active material and aggregation of generated products. Benefiting from the synergistic effects of the well-designed heterostructure and PPy-coated nanotube-like architecture, the prepared Mo3S4/CoMo2S4 heterostructure delivers high reversible capacity (1251.3 mAh g-1 at 300 mA g-1), superior rate performance (340.3 mAh g-1 at 5.0 A g-1) and excellent cycling lifespan (744.1 mAh g-1 after 600 cycles at a current density of 2.0 A g-1). Such a design concept provides a promising strategy towards heterostructure materials to enhance their lithium storage performances and boost their practical applications.

20.
Ecotoxicol Environ Saf ; 247: 114247, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332408

RESUMO

Antibiotic resistance bacteria (ARB) and antibiotic resistance genes (ARGs) are emerging contaminants posing risk to human health. To investigate the pathogenic ARBs and the horizontal gene transfer (HGT) via both extracellular ARGs (eARGs) and intracellular ARGs (iARGs), an in vitro digestion simulation system was established to monitoring the ARB and ARGs passing through the artificial digestive tract. The results showed that ARB was mostly affected by the acidity of the gastric fluid with about 99% ARB (total population of 2.45 × 109-2.54 × 109) killed at pH 2.0 and severe damage of bacterial cell membrane. However, more than 80% ARB (total population of 2.71 × 109-3.90 × 109) survived the challenge when the pH of the gastric fluid was 3.0 and above. Most ARB died from the high acidity, but its ARGs, intI1 and 16 S rRNA could be detected. The eARGs (accounting for 0.03-24.56% of total genes) were less than iARGs obviously. The eARGs showed greater HGT potential than that of iARGs, suggesting that transformation occurred more easily than conjugation. The transferring potential followed: tet (100%) > sul (75%) > bla (58%), related to the high correlation of intI1 with tetA and sul2 (p < 0.01). Moreover, gastric juice of pH 1.0 could decrease the transfer frequency of ARGs by 2-3 order of magnitude compared to the control, but still posing potential risks to human health. Under the treatment of digestive fluid, ARGs showed high gene horizontal transfer potential, suggesting that food-borne ARBs pose a great risk of horizontal transfer of ARGs to intestinal bacteria.


Assuntos
Antagonistas de Receptores de Angiotensina , Transferência Genética Horizontal , Humanos , Antibacterianos/farmacologia , Inibidores da Enzima Conversora de Angiotensina , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Digestão
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