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1.
Front Microbiol ; 15: 1390331, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841064

RESUMO

This study investigated the effect of nitrogen application on the rhizosphere soil microenvironment of sunflower and clarified the relationship between ammonium assimilation and the microenvironment. In a field experiment high (HN, 190 kg/hm2), medium (MN, 120 kg/hm2) and low nitrogen (CK, 50 kg/hm2) treatments were made to replicate plots of sunflowers using drip irrigation. Metagenomic sequencing was used to analyze the community structure and functional genes involved in the ammonium assimilation pathway in rhizosphere soil. The findings indicated that glnA and gltB played a crucial role in the ammonium assimilation pathway in sunflower rhizosphere soil, with Actinobacteria and Proteobacteria being the primary contributors. Compared with CK treatment, the relative abundance of Actinobacteria increased by 15.57% under MN treatment, while the relative abundance decreased at flowering and maturation stages. Conversely, the relative abundance of Proteobacteria was 28.57 and 61.26% higher in the MN treatment during anthesis and maturation period, respectively, compared with the CK. Furthermore, during the bud stage and anthesis, the abundance of Actinobacteria, Proteobacteria, and their dominant species were influenced mainly by rhizosphere soil EC, ammonium nitrogen (NH4+-N), and nitrate nitrogen (NO3--N), whereas, at maturity, soil pH and NO3--N played a more significant role in shaping the community of ammonium-assimilating microorganisms. The MN treatment increased the root length density, surface area density, and root volume density of sunflower at the bud, flowering, and maturity stages compared to the CK. Moreover, root exudates such as oxalate and malate were positively correlated with the dominant species of Actinobacteria and Proteobacteria during anthesis and the maturation period. Under drip irrigation, applying 120 kg/hm2 of nitrogen to sunflowers effectively promoted the community structure of ammonium-assimilating microorganisms in rhizosphere soil and had a positive influence on the rhizosphere soil microenvironment and sunflower root growth.

2.
Adv Mater ; : e2402391, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669588

RESUMO

High-entropy alloy nanoparticles (HEAs) show great potential in emerging electrocatalysis due to their combination and optimization of multiple elements. However, synthesized HEAs often exhibit a weak interface with the conductive substrate, hindering their applications in long-term catalysis and energy conversion. Herein, a highly active and durable electrocatalyst composed of quinary HEAs (PtNiCoFeCu) encapsulated inside the activated carbonized wood (ACW) is reported. The self-encapsulation of HEAs is achieved during Joule heating synthesis (2060 K, 2 s) where HEAs naturally nucleate at the defect sites. In the meantime, HEAs catalyze the deposition of mobile carbon atoms to form a protective few-layer carbon shell during the rapid quenching process, thus remarkably strengthening the interface stability between HEAs and ACW. As a result, the HEAs@ACW shows not only favorable activity with an overpotential of 7 mV at 10 mA cm-2 for hydrogen evolution but also negligible attenuation during a 500 h stability test, which is superior to most reported electrocatalysts. The design of self-encapsulated HEAs inside ACW provides a critical strategy to enhance both activity and stability, which is also applicable to many other energy conversion technologies.

3.
Small ; 19(26): e2206798, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37010010

RESUMO

The oxygen evolution reaction (OER) has significant effects on the water-splitting process and rechargeable metal-air batteries; however, the sluggish reaction kinetics caused by the four-electron transfer process for transition metal catalysts hinder large-scale commercialization in highly efficient electrochemical energy conversion devices. Herein, a magnetic heating-assisted enhancement design for low-cost carbonized wood with high OER activity is proposed, in which Ni nanoparticles are encapsulated in amorphous NiFe hydroxide nanosheets (a-NiFe@Ni-CW) via direct calcination and electroplating. The introduction of amorphous NiFe hydroxide nanosheets optimizes the electronic structure of a-NiFe@Ni-CW, accelerating electron transfer and reducing the energy barrier in the OER. More importantly, the Ni nanoparticles located on carbonized wood can function as magnetic heating centers under the effect of an alternating current (AC) magnetic field, further promoting the adsorption of reaction intermediates. Consequently, a-NiFe@Ni-CW demonstrated an overpotential of 268 mV at 100 mA cm-2 for the OER under an AC magnetic field, which is superior to that of most reported transition metal catalysts. Starting with sustainable and abundant wood, this work provides a reference for highly effective and low-cost electrocatalyst design with the assistance of a magnetic field.

4.
Medicine (Baltimore) ; 99(31): e20960, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32756082

RESUMO

BACKGROUND: The number of children with nonalcoholic fatty liver disease (NAFLD) is proliferating. However, currently, there are no drugs approved for the management of NAFLD. There have been some studies on vitamin D and NAFLD in children. However, the effectiveness of vitamin D in children with NAFLD has not been systematically evaluated. The objective of this systematic review will be to evaluate the effectiveness of vitamin D in children with NAFLD. METHODS: We will search through PubMed, Google Scholar, Cochrane Library, Web of Science, and the ClinicalTrials.gov website without restriction on publishing status. To supplement our search strategy, we will scan the reference lists of the identified studies for detailed evaluation for additional possible eligible studies, and we will also search conference proceedings related to this topic. All databases were searched from inception to present. Any clinical randomized controlled trials related to vitamin D supplement for treating NAFLD (simple steatosis/NAFL and NASH) in children will be included. NAFLD had to be diagnosed by liver histology, imaging (ultrasound, computer tomography, magnetic resonance imaging). The primary outcomes will be changes in liver fibrosis and liver enzymes. The variations in serum vitamin D level, BMI, insulin levels, lipid profiles, liver fat content will also be assessed. All statistical analyses will be carried out using RevMan, version 5.3, Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014. RESULTS: This study will provide a comprehensive high-quality synthesis to evaluate the effectiveness of vitamin D supplementation in children with NAFLD. CONCLUSION: This systematic review and meta-analysis will provide evidence to judge whether vitamin D supplementation is an effective intervention for children with NAFLD. REGISTRATION NUMBER: INPLASY202050049.


Assuntos
Suplementos Nutricionais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Criança , Humanos , Resultado do Tratamento , Metanálise como Assunto
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