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1.
J Colloid Interface Sci ; 663: 177-190, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38401439

RESUMO

The treatment of wastewater containing hypophosphite [P(I)] and phosphite [P(III)] is challenged by limitations of traditional Fenton oxidation such as low efficiency, secondary pollution and high costs. This study introduced a facile solvent-thermal method to synthesize Cu-Co3O4 nanoparticles uniformly loaded on graphene (Cu-Co3O4/U-rGO) through the reduction and coordination effects of urushiol (U). As prepared Cu-Co3O4/U-rGO exhibited excellent activity in activating peroxymonosulfate (PMS) for the oxidation of P(I)/P(III) to phosphate [P(V)] (0.229 min-1), along with high stability and reusability (91.5 % after 6 cycles), low metal leaching rate (Co: 0.2 mg/L, Cu: 0.05 mg/L), insensitivity to common anions in water and a wide pH range (3-11). The activation mechanism involved the synergistic effects from both urushiol and graphene, which promoted redox of Cu+/Cu2+ and Co2+/Co3+ and induced abundant oxygen vacancies for PMS activation to produce singlet oxygen. Furthermore, the Cu-Co3O4/U-rGO/PMS was also excellent in the oxidative removal of organic phosphorus. This study is expected to advance strategies for the treatment of P(I)/P(III)-rich wastewater and provide new insights for the development of low-cost, highly efficient heterogeneous catalysts with abundant oxygen vacancies.

2.
Int J Numer Method Biomed Eng ; 40(3): e3807, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38281812

RESUMO

Endovascular coiling is the predominant method for treating cerebral aneurysms. Extensive reports on selecting coil length, hardness, and material are available. However, the impact of coil diameter on postoperative outcomes remains unclear. This study enrolled six personalized geometric models of intracranial aneurysms: three bifurcation aneurysms and three sidewall aneurysms. Four coil models were constructed by changing the coil diameter. Coil embolization was simulated using the finite element method. Computational fluid dynamics was used to characterize hemodynamics in the aneurysms after embolization. Evaluation parameters included velocity reduction, wall shear stress (WSS), low WSS (LWSS), oscillatory shear index (OSI), relative residence time (RRT), and residual flow volume in the aneurysms. At the peak time (t = 0.17 s), the proportion of LWSS area in bifurcation aneurysms increase with the rise in coil diameter: 0.8D, 71.28 ± 12.62% versus 1D, 74.97 ± 19.17% versus 1.2D, 78.88 ± 18.56% versus 1.4D, 84.00 ± 11.53% (mean ± SD). The proportion of high OSI area decreases as the coil diameter increases: 0.8D, 4.41% ± 2.82% versus 1.0D, 3.78 ± 3.33% versus 1.2D, 2.28% ± 1.77% versus 1.4D, 1.58% ± 1.11% (mean ± SD). The proportion of high RRT area increases as the coil diameter rises: 0.8D, 3.40% ± 1.68% versus 1.0D, 7.67 ± 4.12% versus 1.2D, 9.84% ± 9.50% versus 1.4D, 22.29% ± 14.28% (mean ± SD). Side wall aneurysms do not exhibit the aforementioned trend. Bifurcation aneurysms plugged with a coil of 1.4 times the diameter have the largest RFVs (<10 mm/s) within the group. Aforementioned patterns are not found in sidewall aneurysms. In the treatment of aneurysms with coiling, varying coil diameters can result in different hemodynamic environments within the aneurysm. Larger coil diameters have improved hemodynamic performance for bifurcation aneurysms. However, coil diameter and embolization effectiveness have no significant relationship for sidewall aneurysms.


Assuntos
Embolização Terapêutica , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/cirurgia , Hemodinâmica , Prótese Vascular , Embolização Terapêutica/métodos , Hidrodinâmica
3.
ACS Appl Mater Interfaces ; 15(33): 39905-39914, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37567567

RESUMO

Ionic diode based devices or circuits can be applied, for example, in electroosmotic pumps or in desalination processes. Aquivion ionomer coated asymmetrically over a Teflon film (5 µm thickness) with a laser-drilled microhole (approximately 10 µm diameter) gives a cationic diode with a rectification ratio of typically 10-20 (measured in 0.01 M NaCl with ±0.3 V applied bias). Steady state voltammetry, chronoamperometry, and electrochemical impedance spectroscopy data are employed to characterize the ionic diode performance parameters. Next, a COMSOL 6.0 finite element model is employed to quantitatively assess/compare transient phenomena and to extract mechanistic information by comparison with experimental data. The experimental diode time constant and diode switching process associated with a distorted semicircle (with a typical diode switching frequency of 10 Hz) in the Nyquist plot are reproduced by computer simulation and rationalized in terms of microhole diffusion-migration times. Fundamental understanding and modeling of the ionic diode switching process can be exploited in the rational/optimized design of new improved devices.

4.
ACS Appl Mater Interfaces ; 15(36): 42369-42377, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37638824

RESUMO

Molecularly rigid polymers with internal charges (positive charges induced by amine methylation) allow electroosmotic water flow to be tuned by adjusting the charge density (the degree of methylation). Here, a microporous polyamine (PIM-EA-TB) is methylated to give a molecularly rigid anion conductor. The electroosmotic drag coefficient (the number of water molecules transported per anion) is shown to increase with a lower degree of methylation. Net water transport (without charge flow) in a coupled anionic diode circuit is demonstrated based on combining low and high electroosmotic drag coefficient materials. The AC-electricity-driven net process offers water transport (or transport of other neutral species, e.g., drugs) with net zero ion transport and without driver electrode side reactions.

5.
Trop Anim Health Prod ; 53(6): 555, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34853935

RESUMO

The significance of microbial community structure has been extensively recognized due to its key roles in metabolism, immunity, and health maintenance. Importantly, increasing evidence indicated that the dynamic distribution of microbial community structure can be used for evaluating the health condition of host. Yaks (Bos grunniens), mainly inhabiting in high-altitude hypoxic environment, are characterized by excellent adaptability and strong resistance. Currently, it has been determined that yaks possessed the complicated gastrointestinal microbial ecosystem, whereas not much is known about the nasal microbial community structure of yaks. Therefore, this study was performed to compare and analyze the differences in nasal microbiota of yaks with different ages by high-throughput sequencing. In this study, a total of 487,168 and 486,498 high-quality sequences were achieved from YYG (1-month-old yaks) and AYG (1-year-old yaks), respectively. Additionally, 5,340 operational taxonomic units (OTUs) were identified and 657 OTUs were in common among all samples. Proteobacteria and Firmicutes were the two most predominant phyla in all samples. Moreover, Actinobacteria and Bacteroidetes were the tertiary dominant phyla in YYG and AYG, respectively. At the level of genus, Moraxella, Faucicola, and Mannheimia were the most preponderant bacterial genera in the young and adult yaks. As compared to the AYG, the proportions of Actinobacillus, Parabacteroides, and Haemophilus in the YYG were significantly increased, whereas the Rhizobacter was decreased. In conclusion, this study firstly compared and investigated the distribution of nasal microbiota in yaks with different ages. Results demonstrated that age was an important factor affecting the nasal microbiota. Moreover, the current study will provide a theoretical basis for the further study on the microbial community structure of yaks.


Assuntos
Microbiota , Animais , Bactérias , Bovinos
6.
Microb Cell Fact ; 19(1): 123, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503532

RESUMO

BACKGROUND: The gut microbiota is a complex ecosystem, which is essential for the metabolism, health and immunity of host. Many diseases have been shown to be closely related to the alteration of intestinal flora. Aeromonas veronii as a conditioned pathogen can cause disease in Yangtze finless porpoise through intestinal infections. However, it is not clear whether the disease caused by Aeromonas veronii is related to changes of intestinal flora. In the current study, the diversity and composition of gut microbiota in the healthy and Aeromonas veronii-infected Yangtze finless porpoise were evaluated by high-throughput sequencing to further investigate the potential association between intestinal flora alteration and pathogen invasion. RESULTS: A total of 127,3276 high-quality sequences were achieved and 2465 operational taxonomic units (OTUs) were in common among all samples. The results of alpha diversity showed that there was no obvious difference in richness and diversity between healthy and Aeromonas veronii-infected Yangtze finless porpoise. Firmicutes, Bacteroidetes and Proteobacteria were the most dominant phyla in all samples. In addition, the healthy Yangtze finless porpoise exhibited higher abundance of Firmicutes and Fusobacteria than Aeromonas veronii-infected Yangtze finless porpoise, while, the level of Proteobacteria was decreased. At the genus level, Paeniclostridium and Paraclostridium were the predominant bacteria genera in the CK (healthy Yangtze finless porpoise) group. In the DIS (Aeromonas veronii-infected Yangtze finless porpoise) group, Lactobacillus and unidentified_Enterobacteriaceae were the dominant bacteria genera and the proportion of Paeniclostridium, Paraclostridium, Terrisporobacter, Cetobacterium, Candidatus Arthromitus, Terrabacter and Dechloromonas were reduced. CONCLUSIONS: In conclusion, our results showed that Aeromonas veronii infection can alter the gut microbiota of the Yangtze finless porpoise by affecting the number of harmful bacteria and beneficial bacteria.


Assuntos
Aeromonas veronii , Bactérias , Microbioma Gastrointestinal , Infecções por Bactérias Gram-Negativas , Toninhas/microbiologia , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , China , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária
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