Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros

Banco de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Water Sci Technol ; 88(3): 517-529, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37578871

RESUMEN

Magnetic fields positively influence the nitrogen removal efficiency in activated sludge systems. However, the structural succession pattern of microorganisms by magnetic fields still remains further explored. In this paper, a magnetic simultaneous nitrification and denitrification (MSND) reactor was constructed, and the influence of optimized magnetic field intensity (0, 10, 20 and 30 mT) on the nitrogen removal efficiency was investigated at HRT 6 h, 28.0-30.0 °C, and pH 7.0-8.0. Molecular biology was used to investigate the succession process of the dominant microbial flora and the functional gene structure of MSND systems. The results showed that the denitrification effects of the MSND system were significantly enhanced, which contributed to the lower concentration of total nitrogen in the effluent of the magnetic reactor than that of the nonmagnetic group reactor. The magnetic fields induced the succession of microbial community structure and improved the stability of microbial communities, thereby the relative abundances of nitrifying and denitrifying bacteria, and the functional genes were improved. In particular, the abundance of functional genes related to gene proliferation and transmembrane transport was increased. Therefore, the efficient nitrogen removal was achieved, which gives inspiration in the enhanced wastewater treatment by magnetic fields.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39016552

RESUMEN

Binders are crucial for maintaining the mechanical stability of the electrodes. However, traditional binders fail to adequately buffer the volume expansion of Zn2SiO4 anode, causing electrode contact failure and considerable capacity loss during cycling. In this study, we propose a simple and effective solution to address these challenges through a combined strategy of hollow structure design and the introduction of an aqueous lithium poly(acrylic acid) (LiPAA) binder. Hollow structures can shorten ion-transfer distance and accommodate volume change outside. The excellent adhesion of the LiPAA binder created a secure connection between the active Zn2SiO4 particles, conductive additives, and the current collector, which enhanced the mechanical stability and integrity of the electrode. As a result of these positive factors, a Zn2SiO4 electrode using LiPAA as a binder can deliver an excellent capacity of 499 mAh g-1 at a high current density of 5 A g-1 and a long life span of 1000 cycles at 1 A g-1 with a capacity retention of 98%, which significantly outperforms other binders. As demonstrated by ex situ X-ray diffraction and ex situ X-ray absorption spectroscopy, the storage of lithium ions in Zn2SiO4 follows a dual conversion-alloying mechanism, using Zn as the redox center. In this process, Zn is first reduced to metallic Zn and then forms a LiZn alloy upon lithium-ion insertion. This work shows that LiPAA offers a promising approach to improve the cycling longevity of conversion and alloying anodes in Li-ion batteries.

3.
Chemosphere ; 339: 139532, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37467854

RESUMEN

In this study, H2S was used as a partial replacement nutrient substrate for sludge bioleaching. The effects of different combinations of H2S/sludge load and monomeric sulphur on heavy metal removal and microbial communities were investigated. Changes in pH, oxidation-reduction potential (ORP), SO42- concentration, heavy metal removal, and the content of heavy metal states during bioleaching were investigated, and community diversity analysis was performed. Daily introduction of H2S three times (at an interval of 8 h) at a gas flow rate of 2 ml/min and an H2S/sludge load of 15 ml/L with 5 g/L FeSO4·7H2O and 2 g/L monomeric sulphur as a nutrient substrate significantly accelerated both the bioleaching process and the pH drop in the sludge system, promoted the production of SO42-, and maintained a higher redox potential. The combination of H2S and monomeric sulphur had a significant effect on the leaching of heavy metals. Compared with the experimental group containing only H2S or monomeric sulphur, the removal rates of Zn, Ni, Pb, and Cr increased by 4.63%/13.8%, 8.5%/20.07%, 3.84%/9.5%, and 4.24%/8.02% respectively, while promoting the transformation of various heavy metal states to labile states, improving heavy metal stability, and reducing sludge ecotoxicity. High-throughput sequencing analysis showed that introducing the H2S gaseous matrix accelerated the decreasing trend of species number, bacterial abundance, and community diversity in the sludge system, promoting Proteobacteria as the dominant phylum, Acidithiobacillus, Metallibacterium, and Thiomonas as the dominant genera, and improving the bioleaching treatment effect.


Asunto(s)
Acidithiobacillus , Metales Pesados , Aguas del Alcantarillado/química , Concentración de Iones de Hidrógeno , Azufre , Metales Pesados/análisis
4.
Front Neurol ; 12: 645431, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33995249

RESUMEN

Background: Stent retriever thrombectomy is the standard treatment for acute ischemic stroke (AIS) with large vessel occlusion (LVO) in anterior circulation. The aim of the trial is to evaluate whether the new thrombectomy device-Skyflow can achieve the same safety and efficacy as Solitaire FR in the treatment. Method: This study is a prospective, multicenter, stratified randomized, single blind, paralleled, positive controlled, non-inferiority clinical trial. The safety and efficacy of vascular recanalization in AIS patients who are treated with either a new thrombectomy device-Skyflow or with Solitaire FR and within 8 h of symptom onset will be compared. A total of 192 patients will be enrolled, each group with 96 patients. The primary endpoint is successful recanalization rate after the operation. The secondary efficacy endpoints are the time from artery puncture to successful recanalization (mTICI 2b-3), NIHSS scores of 24 h (18-36 h), and 7 ± 2 days after the operation, mRS scores, and the rate of patients with mRS 0-2 scores 90 ± 14 days after the operation, and the success rate of instrument operation. The safety endpoints are the rate of symptomatic intracranial hemorrhage (sICH) and subarachnoid hemorrhage at 24 h (18-36 h) post-operation, incidence of adverse events (AE) and serious adverse events (SAE), all-cause mortality, and incidence of device defects. Discussion: This trial will provide information on the safety and efficacy of Sky-flow stent retriever in the treatment of AIS patients with anterior circulation LVO. The success of this trial will be the basis for the product to be finally officially listed and applied in China. Trial registration: Registered on 11 March 2018 with Chinese clinical trial registry. Registration number is ChiCTR1800015166.

5.
J Agric Food Chem ; 69(49): 14824-14839, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34851635

RESUMEN

Metabolic dysfunction (MD) is a major health problem threatening the life quality of menopausal women. Saffron has been widely used in herb prescriptions for treating menopausal syndrome. However, the pharmacological effects and mechanisms of saffron are poorly understood. Here, we investigated the effect of crocin, the major ingredient of saffron and its active metabolite in blood, crocetin, on MD and lipid metabolism in ovariectomized (OVX) mice and 3T3-L1 adipocytes. The present study showed that intragastric treatment of crocin prevented weight gain, fat accumulation, and insulin resistance in OVX mice by increasing energy expenditure and fat oxidation. Mechanistically, crocin influenced adipose tissue homeostasis by regulating adipogenic and lipolytic factors, which was strongly associated with the restoration of the downregulated ERß function in white adipose tissue (WAT). In vitro, crocetin facilitated lipid metabolism in an ERß-dependent manner. Our results demonstrated the beneficial effects of crocetin/crocin-mediated intervention against metabolic dysfunction, revealing a prospective therapeutic application in menopausal women.


Asunto(s)
Carotenoides/farmacología , Crocus , Receptor beta de Estrógeno , Ovariectomía/efectos adversos , Vitamina A/farmacología , Tejido Adiposo Blanco , Animales , Crocus/química , Receptor beta de Estrógeno/genética , Femenino , Ratones , Vitamina A/análogos & derivados
6.
Dis Model Mech ; 14(12)2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34821368

RESUMEN

Skeletal muscle regeneration requires extracellular matrix (ECM) remodeling, including an acute and transient breakdown of collagen that produces gelatin. Although the physiological function of this process is unclear, it has inspired the application of gelatin to injured skeletal muscle for a potential pro-regenerative effect. Here, we investigated a bi-phasic effect of gelatin in skeletal muscle regeneration, mediated by the hormetic effects of reactive oxygen species (ROS). Low-dose gelatin stimulated ROS production from NADPH oxidase 2 (NOX2) and simultaneously upregulated the antioxidant system for cellular defense, reminiscent of the adaptive compensatory process during mild stress. This response triggered the release of the myokine IL-6, which stimulates myogenesis and facilitates muscle regeneration. By contrast, high-dose gelatin stimulated ROS overproduction from NOX2 and the mitochondrial chain complex, and ROS accumulation by suppressing the antioxidant system, triggering the release of TNFα, which inhibits myogenesis and regeneration. Our results have revealed a bi-phasic role of gelatin in regulating skeletal muscle repair mediated by intracellular ROS, the antioxidant system and cytokine (IL-6 and TNFα) signaling.


Asunto(s)
Gelatina , Desarrollo de Músculos , Gelatina/metabolismo , Gelatina/farmacología , Músculo Esquelético/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Regeneración , Cicatrización de Heridas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA