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1.
J Biol Chem ; : 107773, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276929

RESUMO

Parkinson's disease (PD) is a multi-factorial neurodegenerative disorder. Loss or degeneration of the dopaminergic neurons in the substantia nigra and development of Lewy Bodies in dopaminergic neurons were the defining pathologic changes. MiRNAs fine-tune the protein levels by post-transcriptional gene regulation. MiR-7019-3p is encoded within the 5th intron of PD associated protein PINK1. In present study, we firstly demonstrated miR-7019-3p expression is significantly up regulated in PD mice model and neuron cell models, miR-7019-3p mainly existed in mitochondria, miR-7019-3p could regulate the structure and function of mitochondria in neuronal cells. We predicted and verified that mitochondria associated protein OPA1 and 12s rRNA, 16s rRNA and polycistronic RNA are target genes of miR-7019-3p. Finally, we proved that SP1 protein could independently regulate the expression of miR-7019-3p at the upstream. The evidences in the study suggest the role miR-7019-3p in the regulation of mitochondrial structure and function, and this kind of regulation could be implemented or promoted through the pathway of SP1-miR-7019-3p-OPA1/12s rRNA, 16s rRNA and polycistronic RNA. Our results have suggested a promising and potential therapeutic target for reversing mitochondria dysregulation in neuronal cells during Parkinson's disease process.

2.
Heliyon ; 10(13): e33869, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39044961

RESUMO

In this study, the loss of quality from the oxidative thermal decomposition of jute fiber was explored during the production of reinforced composite materials. Amino silicone oil was used to modify jute fiber, which was then subjected to thermogravimetric analysis. The modified fiber's thermal decomposition temperature was found to be 271 °C, enhancing the composite's thermal stability. The study also investigated how different jute fiber content affected the mechanical and sound absorption properties of composite materials. Results showed that jute fiber composites had better mechanical properties than pure polypropylene materials, and the average sound absorption coefficient of jute polypropylene composites increased with fiber content. Adding jute fiber to polypropylene effectively improved the sound absorption and noise reduction performance of the material. The average sound absorption coefficient of the composite material at a mass content of 20 wt% was 120 % higher than that of the polypropylene matrix material.

3.
Huan Jing Ke Xue ; 44(9): 5006-5016, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699818

RESUMO

For resolving the problems of poor nitrogen removal efficiency and substandard effluent quality in wastewater treatment plants during winter, a cold-tolerant strain Glutamicibacter sp. WS1, with heterotrophic nitrification-aerobic denitrification ability, was isolated from activated sludge. The functional genes for nitrogen conversion of strain WS1 were amplified by PCR, and the nitrogen removal characteristics of the strain were verified under different nitrogen sources at 15℃. In addition, the effects of environmental factors on the aerobic denitrification performance of the strain were explored at low temperature. Finally, a reasonable nitrogen metabolism pathway of strain WS1 was resolved based on functional genes and nitrogen balance analysis. The results showed that strain WS1 contained functional genes related to nitrogen conversion, including amoA, napA, nirS, and nirK genes. Notably, nirS and nirK genes coexisted in the strain. At the low temperature of 15℃, with NH4+-N, NO3--N, NO2--N+NO3--N, and NH4+-N+NO3--N as nitrogen sources, the corresponding removal efficiencies of strain WS1 were 100%, 98.10%, 99.87%+100%, and 100%+94.92%, respectively. The optimal denitrification performance of the strain was achieved with sodium citrate as the carbon source, C/N of 16, pH of 8, DO of 4.5-6.8 mg·L-1, and temperature of 30℃. In addition, the NO3--N removal efficiency of strain WS1 reached 92.50% under low temperature (15℃) and low C/N (10) conditions. Based on the results of PCR amplification and nitrogen balance analysis, heterotrophic nitrification-aerobic denitrification/aerobic denitrification and assimilation were the main pathways for nitrogen substrate removal by strain WS1, in which most of the inorganic nitrogen (47%-56%) was converted to gaseous nitrogen through heterotrophic nitrification-aerobic denitrification/aerobic denitrification. Strain WS1 has broad application prospects in the treatment of low-temperature nitrogenous wastewater.


Assuntos
Desnitrificação , Nitrogênio , Temperatura , Nitrificação , Bactérias
4.
Front Optoelectron ; 16(1): 15, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37318647

RESUMO

Infrared photovoltaic cells (IRPCs) have attracted considerable attention for potential applications in wireless optical power transfer (WOPT) systems. As an efficient fiber-integrated WOPT system typically uses a 1550 nm laser beam, it is essential to tune the peak conversion efficiency of IRPCs to this wavelength. However, IRPCs based on lead sulfide (PbS) colloidal quantum dots (CQDs) with an excitonic peak of 1550 nm exhibit low short circuit current (Jsc) due to insufficient absorption under monochromatic light illumination. Here, we propose comprehensive optical engineering to optimize the device structure of IRPCs based on PbS CQDs, for 1550 nm WOPT systems. The absorption by the device is enhanced by improving the transmittance of tin-doped indium oxide (ITO) in the infrared region and by utilizing the optical resonance effect in the device. Therefore, the optimized device exhibited a high short circuit current density of 37.65 mA/cm2 under 1 sun (AM 1.5G) solar illumination and 11.91 mA/cm2 under 1550 nm illumination 17.3 mW/cm2. Furthermore, the champion device achieved a record high power conversion efficiency (PCE) of 7.17% under 1 sun illumination and 10.29% under 1550 nm illumination. The PbS CQDs IRPCs under 1550 nm illumination can even light up a liquid crystal display (LCD), demonstrating application prospects in the future.

5.
J Phys Chem Lett ; 13(51): 11892-11898, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36524775

RESUMO

Orbital mixing is paramount to chemistry as it plays a central role in bond formation. It is also important for technologies such as molecular doping of polymers, where the concept of fractional charge transfer is essentially orbital mixing between dopants and hosts. Likewise, it would be both fundamentally interesting and technologically relevant to investigate orbital mixing in emerging hybrid materials containing both inorganic and organic moieties. Here we report experimental observation of orbital mixing between valence band levels of strongly confined PbS quantum dots (QDs) and lowest unoccupied molecular levels of surface-bound high-electron affinity molecules (F4TCNQ), manifested as both an absorption blue-shift of PbS and the emergence of visible and infrared signatures of the fractional charge-transfer species of F4TCNQ. The degree of mixing can be controlled by varying the QD size or by varying the molecule/QD ratio for a specific QD size and can be quantitatively reproduced by a nondegenerate, two-level perturbation model.

6.
Bioresour Technol ; 362: 127756, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35952861

RESUMO

For improving the poor de-nitrogen efficiency and effluent quality faced by wastewater treatment plants in winter, a novel cold-resistant strain, Rhizobium sp. WS7 was isolated. Strain WS7 presented dramatic de-nitrogen efficiencies including 98.73 % of NH4+-N, 99.98 % of NO3--N, 100 % of NO2--N and approximately 100 % of mixed nitrogen (NH4+-N and NO3--N) at 15 °C. Optimum parameters of WS7 for aerobic denitrification were determined. Additionally, functional genes (amoA, napA, nirK, norB, and nosZ) and key enzymes (nitrate reductase and nitrite reductase) activities were determined. Nitrogen balance analysis suggested that assimilation played a dominant role in de-nitrogen by WS7, the NH4+-N metabolic pathway was deduced as NH4+-N â†’ NH2OH â†’ NO â†’ N2O â†’ N2, and the NO3--N/NO2--N metabolic pathway was deduced as NO3--N â†’ NO2--N â†’ NO â†’ N2O â†’ N2. The cold-resistant Rhizobium sp. WS7 has great application feasibility in cold sewage treatment.


Assuntos
Nitrificação , Rhizobium , Aerobiose , Desnitrificação , Processos Heterotróficos , Nitritos/metabolismo , Nitrogênio/metabolismo , Dióxido de Nitrogênio , Rhizobium/metabolismo
7.
Environ Pollut ; 265(Pt B): 114865, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32505961

RESUMO

In-site remediation is a relatively promising and socially acceptable technique for heavy metal contaminated soils. But the key task is to select cost-effective and environment-friendly amendents for the consideration of practical application. Based on the property of four typical silicate wastes such as straw ash (SA), coal fly ash (CFA), ferronickel slag (FNS) and blast-furnace slag (BFS), effects of four wastes on available Cd content and Cd chemical speciation in amended soils, and physicochemical properties of the amended soils were carried out in the study. The results showed that four wastes were dominately composed of the amorphous phases with OH- ions readily released. When the weight ratio of silicate wastes to artificial Cd-contaminated soils reached 10%, the available Cd contents decreased from 4.12 mg/kg in untreated soils to 1.94, 1.92, 1.45 and 1.53 mg/kg in amended soils by adding SA, CFA, FNS and BFS respectively, after the soils were amended for 30 days. The residual fraction of Cd (R) was 2.54, 2.48, 2.77 and 2.58 times higher in amended soil than that in untreated soil when SA, CFA, FNS and BFS was added, respentively. The soil pH and CEC were improved. The amended soils by adding SA and FNS were looser than those by adding CFA and BFS, and air permeability of the amended soils by SA was better than that by FNS.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo/análise , Cádmio/análise , Estudos de Viabilidade , Silicatos , Solo
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