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1.
Environ Pollut ; 344: 123344, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38215869

RESUMO

Nutrient enrichment, such as nitrogen (N) and phosphorus (P), typically affects nitrous oxide (N2O) emissions in terrestrial ecosystems, predominantly via microbial nitrification and denitrification processes in the soil. However, the specific impact of soil property and microbial community alterations under N and P enrichment on grassland N2O emissions remains unclear. To address this, a field experiment was conducted in an alpine meadow of the northeastern Qinghai-Tibetan Plateau. This study aimed to unravel the mechanisms underlying N and P enrichment effects on N2O emissions by monitoring N2O fluxes, along with analyzing associated microbial communities and soil physicochemical properties. We observed that N enrichment individually or in combination with P enrichment, escalated N2O emissions. P enrichment dampened the stimulatory effect of N enrichment on N2O emissions, indicative of an antagonistic effect. Structural equation modeling (SEM) revealed that N enrichment enhanced N2O emissions through alterations in fungal community composition and key soil physicochemical properties such as pH, ammonium nitrogen (NH4+-N), available phosphorus (AP), microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN)). Notably, our findings demonstrated that N2O emissions were significantly more influenced by fungal activities, particularly genera like Fusarium, rather than bacterial processes in response to N enrichment. Overall, the study highlights that N enrichment intensifies the role of fungal attributes and soil properties in driving N2O emissions. In contrast, P enrichment exhibited a non-significant effect on N2O emissions, which highlights the critical role of the fungal community in N2O emissions responses to nutrient enrichments in alpine grassland ecosystems.


Assuntos
Microbiota , Micobioma , Solo , Pradaria , Microbiologia do Solo , Nitrogênio , Óxido Nitroso/análise , Fósforo
2.
Mikrochim Acta ; 190(7): 260, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37318602

RESUMO

High-throughput screening platforms are fundamental for the rapid and efficient processing of large amounts of experimental data. Parallelization and miniaturization of experiments are important for improving their cost-effectiveness. The development of miniaturized high-throughput screening platforms is essential in the fields of biotechnology, medicine, and pharmacology. Currently, most laboratories use 96- or 384-well microtiter plates for screening; however, they have disadvantages, such as high reagent and cell consumption, low throughput, and inability to avoid cross-contamination, which need to be further optimized. Droplet microarrays, as novel screening platforms, can effectively avoid these shortcomings. Here, the preparation method of the droplet microarray, method of adding compounds in parallel, and means to read the results are briefly described. Next, the latest research on droplet microarray platforms in biomedicine is presented, including their application in high-throughput culture, cell screening, high-throughput nucleic acid screening, drug development, and individualized medicine. Finally, the challenges and future trends in droplet microarray technology are summarized.


Assuntos
Ensaios de Triagem em Larga Escala , Ensaios de Triagem em Larga Escala/métodos , Avaliação Pré-Clínica de Medicamentos , Análise em Microsséries/métodos
3.
ACS Appl Mater Interfaces ; 14(50): 55933-55943, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36480473

RESUMO

All-dielectric structural colors are attracting increasing attention due to their great potential for various applications in display devices, imaging security certification, optical data storage, and so on. However, it remains a great challenge to achieve vivid structural colors with low-aspect-ratio silicon nanostructures directly on a silicon substrate, which is highly desirable for future integrated optoelectronic devices. The main obstacle comes from the difficulty in achieving strong Mie resonances by Si nanostructures on low-index-contrast substrates. Here, we demonstrate a generic principle to create vivid bright field structural colors by using silicon nanopillars directly on top of the silicon substrate. Complementary colors across the full visible spectrum are achieved as a result of the enhanced absorption due to Mie resonances. It is shown that the color saturation increases with the increasing of the nanopillar height. Remarkably, blue and black colors are generated by trapezoid nanopillar arrays as a result of the absorption at long wavelengths or all visible wavelengths. Our strategy provides a powerful scheme for accelerating the integrated optoelectronic applications in nanoscale color printing, imaging, and displays.

4.
Biosensors (Basel) ; 12(10)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36291008

RESUMO

While there are many clinical drugs for prophylaxis and treatment, the search for those with low or no risk of side effects for the control of infectious and non-infectious diseases is a dilemma that cannot be solved by today's traditional drug development strategies. The need for new drug development strategies is becoming increasingly important, and the development of new drugs from traditional medicines is the most promising strategy. Many valuable clinical drugs have been developed based on traditional medicine, including drugs with single active ingredients similar to modern drugs and those developed from improved formulations of traditional drugs. However, the problems of traditional isolation and purification and drug screening methods should be addressed for successful drug development from traditional medicine. Advances in microfluidics have not only contributed significantly to classical drug development but have also solved many of the thorny problems of new strategies for developing new drugs from traditional drugs. In this review, we provide an overview of advanced microfluidics and its applications in drug development (drug compound synthesis, drug screening, drug delivery, and drug carrier fabrication) with a focus on its applications in conventional medicine, including the separation and purification of target components in complex samples and screening of active ingredients of conventional drugs. We hope that our review gives better insight into the potential of traditional medicine and the critical role of microfluidics in the drug development process. In addition, the emergence of new ideas and applications will bring about further advances in the field of drug development.


Assuntos
Medicina Tradicional , Microfluídica , Composição de Medicamentos , Desenvolvimento de Medicamentos , Portadores de Fármacos
5.
ACS Appl Mater Interfaces ; 13(3): 4364-4373, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33390005

RESUMO

Structural coloration with artificially nanostructured materials is emerging as a prospective alternative to traditional pigments for the high resolution, sustainable recycling, and long-time durability. However, achieving bright field structural colors with dielectric nanostructures remains a great challenge due to the weak scattering in an asymmetric environment. Here, we demonstrate all-dielectric bright field structural colors with diffraction-limited resolution on the silicon-on-insulator platform. The backscattering is strongly enhanced from the constructive interference between Mie resonances of individual Si antennas and Fabry-Perot resonances supported by the SiO2 layer. The fabricated colors with varying hues and saturations show strong insensitivity with respect to the interparticle spacing and, remarkably, the viewing angle under resonant conditions. Compared with creating a quasi-homogeneous environment, our strategy is solid and complementary metal-oxide semiconductor integrable, paving the way for practical applications of structural colors in nanoscale color printing, microdisplays, and imaging.

6.
PLoS One ; 10(12): e0144842, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26658644

RESUMO

There has been an upsurge of green reductants for the preparation of graphene materials taking consideration of human health and the environment in recent years. In this paper, reduced graphene oxides (RGOs) were prepared by chemical reduction of graphene oxide (GO) with three green reductants, L-ascorbic acid (L-AA), D-glucose (D-GLC) and tea polyphenol (TP), and comparatively characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectra, Raman spectra and electrical conductivity analysis. Results showed that all these three reductants were effective to remove oxygen-containing functional groups in GO and restore the electrical conductivity of the obtained RGO. The RGO sample with L-ascorbic acid as a reductant and reduced with the existence of ammonia had the highest electrical conductivity (9.8 S·cm(-1)) among all the obtained RGO samples. The mechanisms regarding to the reduction of GO and the dispersion of RGO in water were also proposed. It is the good dispersibility of reduced graphene oxide in water that will facilitate its further use in composite materials and conductive ink.


Assuntos
Ácido Ascórbico/química , Glucose/química , Grafite/química , Polifenóis/química , Substâncias Redutoras/química , Camellia sinensis/química , Condutividade Elétrica , Química Verde , Humanos , Oxirredução , Óxidos , Polifenóis/isolamento & purificação
7.
Nat Prod Res ; 29(18): 1748-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25563135

RESUMO

The aim of this research was to determine the chemical composition of the essential oils of Dahlia pinnata, their insecticidal activity against Sitophilus zeamais and Sitophilusoryzae and to isolate insecticidal constituents. Based on bioactivity-guided fractionation, active constituents were isolated and identified as D-limonene, 4-terpineol and α-terpineol. Essential oils and active compounds tested exhibited contact toxicity, with LD50 values ranging from 132.48 to 828.79 µg/cm(2) against S. zeamais and S. oryzae. Essential oils possessed fumigant toxicity against S. zeamais and S. oryzae with LC50 from 14.10 to 73.46 mg/L. d-Limonene (LC50 = 4.55 and 7.92 mg/L) showed stronger fumigant toxicity against target insects. 4-Terpineol (88 ± 8%) and d-limonene (87 ± 5%) showed the strongest repellency against S. zeamais and S. oryzae, respectively. The results indicate that essential oils and insecticidal constituents have potential for development into natural fumigants, insecticides or repellents for control of the stored-product insect pests.


Assuntos
Dahlia/química , Inseticidas/química , Óleos Voláteis/química , Óleos de Plantas/química , Gorgulhos , Animais , Monoterpenos Cicloexânicos , Cicloexenos/química , Cicloexenos/isolamento & purificação , Limoneno , Mentol/análogos & derivados , Mentol/química , Mentol/isolamento & purificação , Monoterpenos/química , Monoterpenos/isolamento & purificação , Terpenos/química , Terpenos/isolamento & purificação
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