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1.
RSC Adv ; 14(31): 22229-22237, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39010912

RESUMO

Bio-based materials with excellent acoustic absorption properties are in great demand in architecture, interior, and human settlement applications for efficient noise control. In this study, crayfish shells, a form of kitchen waste, are utilized as the primary material to produce ultralight and multifunctional chitin aerogels, which effectively eliminate noise. Different replacement solvents and freezing rates were employed to regulate the porous structures of chitin aerogels, and their resulting acoustic absorption performance was investigated. Results demonstrate that employing deionized water as the replacement solvent and utilizing a common-freeze mode (frozen via refrigerator at -26 °C) can produce chitin aerogels with larger porosity (96.26%) and apertures, as well as thicker pore walls. This results in superior broadband acoustic absorption performance (with a maximum absorption coefficient reaching 0.99) and higher Young's modulus (28 kPa). Conversely, chitin aerogels solvent-exchanged with tert-butyl alcohol or subjected to quick-freeze mode (frozen via liquid nitrogen) exhibit smaller porosity (92.32% and 94.84%) and apertures, thereby possessing stronger diffuse reflection of visible light (average reflectance of 94.30% and 88.18%), and enhanced low-frequency (500 to 1600 Hz) acoustic absorption properties. Additionally, the acoustic absorption mechanism of fabricated chitin aerogels was predicted using a simple three-parameter analysis Johnson-Champoux-Allard-Lafarge (JCAL) model. This study presents a novel approach to developing multifunctional biomass materials with excellent acoustic absorption properties, which could have a wide range of potential applications.

2.
Gels ; 10(2)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38391471

RESUMO

Cellulose aerogels have great prospects for noise reduction applications due to their sustainable value and superior 3D interconnected porous structures. The drying principle is a crucial factor in the preparation process for developing high-performance aerogels, particularly with respect to achieving high acoustic absorption properties. In this study, multifunctional cellulose nanocrystal (CNC) aerogels were conveniently prepared using two distinct freeze-drying principles: refrigerator conventional freezing (RCF) and liquid nitrogen unidirectional freezing (LnUF). The results indicate that the rapid RCF process resulted in a denser CNC aerogel structure with disordered larger pores, causing a stronger compressive performance (Young's modulus of 40 kPa). On the contrary, the LnUF process constructed ordered structures of CNC aerogels with a lower bulk density (0.03 g/cm3) and smaller apertures, resulting in better thermal stability, higher diffuse reflection across visible light, and especially increased acoustic absorption performance at low-mid frequencies (600-3000 Hz). Moreover, the dissipation mechanism of sound energy in the fabricated CNC aerogels is predicted by a designed porous media model. This work not only paves the way for optimizing the performance of aerogels through structure control, but also provides a new perspective for developing sustainable and efficient acoustic absorptive materials for a wide range of applications.

3.
RSC Adv ; 13(41): 28861-28872, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37790098

RESUMO

In this work, five two-dimensional (2D) noble-transition-metal chalcogenide (NTMC) semiconductors, namely ß-NX (N = Au, Ag; X = S, Se, Te), were designed and predicted by first-principles simulations. Structurally, the monolayer ß-NX materials have good energetic, mechanical, dynamical, and thermal stability. They contain two inequivalent noble-transition-metal atoms in the unit cell, and the N-X bond comprises a partial ionic bond and a partial covalent bond. Regarding the electronic properties, the ß-NX materials are indirect-band-gap semiconductors with appropriate band-gap values. They have tiny electron effective masses. The hole effective masses exhibit significant differences in different directions, indicating strongly anisotropic hole mobility. In addition, the coexistence of linear and square-planar channels means that the diffusion and transport of carriers should be anisotropic. In terms of optical properties, the ß-NX materials show high absorption coefficients. The absorption and reflection characteristics reveal strong anisotropy in different directions. Therefore, the ß-NX materials are indirect-band-gap semiconductors with good stability, high absorption coefficients, and strong mechanical, electronic, transport, and optical anisotropy. In the future, they could have great potential as 2D semiconductors in nano-electronics and nano-optoelectronics.

4.
Chem Biol Drug Des ; 102(5): 1202-1212, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37599210

RESUMO

The present study was to investigate the underlying mechanism of the antitumor effect of curcumin in colorectal cancer cells, focusing on the M2 polarization of tumor-associated macrophages (TAMs). The effect of curcumin on the malignant behavior of colorectal cancer cells was investigated by WST assay for cell growth, and Transwell assay for cell migration/invasion. THP-1 cells were differentiated into macrophages and coculture with colorectal cancer cells to study the influence of curcumin on M2 polarization, presenting as the levels of ARG1 mRNA, IL-10, and CD163-positive cells. GEO database was searched for the shared altered gene of curcumin in colorectal cells and human monocytes. Molecular docking was used to visualize the binding between curcumin and MACC1. Curcumin restricted the proliferation, apoptosis, and migration/invasion of HCT 116 and SW620 cells. Curcumin attenuated levels of the M2 macrophage markers, CD163 + cells, IL-10 secretion, and ARG1 mRNA. MACC1 was a target of curcumin in colorectal cancer cells, relating to macrophage. Rescue experiments showed that MACC1 overexpression can reverse the antitumor effect of curcumin in colorectal cancer cells and M2 polarization of TAMs. Curcumin's antiproliferative and anti-migratory effects in colorectal cancer cells may be mediated by MACC1 and inhibition of M2 polarization of TAMs.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Curcumina , Humanos , Interleucina-10/genética , Interleucina-10/farmacologia , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia , Curcumina/farmacologia , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , RNA Mensageiro , Microambiente Tumoral , Transativadores/farmacologia
5.
BMC Oral Health ; 23(1): 121, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36814204

RESUMO

OBJECTIVE: This study aimed to explore the mechanism behind N6-methyladenosine (m6A) modification of the total ribonucleic acid (RNA) involved in the resistance to herpes simplex virus type I (HSV-1) infection in oral epithelial cells. METHOD: The variation in m6A modification level on messenger RNA following HSV-1 infection was determined using the RNA dot blot method. The expression levels of alpha-ketoglutarate-dependent dioxygenase lab homolog 5 (ALKBH5) protein and fatty mass and obesity-associated genes (FTO) were determined using real-time fluorescence quantification polymerase chain reaction and the western blot technique, respectively. Next, after suppressing the expression of ALKBH5 or FTO via small interfering RNA, human immortalised oral epithelial cells (HIOECs) were infected with HSV-1, followed by measurement of the viral load or expression level of type I interferon (I-IFN) and interferon-stimulated genes (ISGs). RESULTS: The m6A modification level was significantly increased following HSV-1 infection of the HIOECs (P < 0.05), while the expression of ALKBH5 and FTO genes was reduced (P < 0.01). Moreover, the suppression of ALKBH5 or FTO increased the production of I-IFN and ISGs during the HSV-1 infection of the HIOECs (P < 0.01), and the viral load was significantly reduced (P < 0.01). CONCLUSION: During oral HSV-1 infection, the m6A level was increased through the down-regulation of ALBHK5 and FTO expression, increasing I-IFN production and the promotion of HSV-1 clearing in HIOECs.


Assuntos
Células Epiteliais , Herpes Simples , RNA , Humanos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Células Epiteliais/metabolismo , RNA/metabolismo , Simplexvirus , Herpes Simples/metabolismo
6.
IEEE Trans Neural Netw Learn Syst ; 34(8): 4321-4331, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34695001

RESUMO

Adaptive inference has been proven to improve bidirectional encoder representations from transformers (BERT)'s inference speed with minimal loss of accuracy. However, current work only focuses on the BERT model and lacks exploration of other pretrained language models (PLMs). Therefore, this article conducts an empirical study on the application of adaptive inference mechanism in various PLMs, including generative pretraining (GPT), GCNN, ALBERT, and TinyBERT. This mechanism is verified on both English and Chinese benchmarks, and experimental results demonstrated that it is able to speed up by a wide range from 1 to 10 times if given different speed thresholds. In addition, its application on ALBERT shows that adaptive inference can work with parameter sharing, achieving model compression and acceleration simultaneously, while the application on TinyBERT proves that it can further accelerate the distilled small model. As for the problem that too many labels make adaptive inference invalid, this article also proposes a solution, namely label reduction. Finally, this article open-sources an easy-to-use toolkit called FastPLM to help developers adopt pretrained models with adaptive inference capabilities in their applications.

7.
Sci Total Environ ; 805: 150058, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34537690

RESUMO

The co-occurrence of cyanobacterial harmful algal blooms and contaminants is an increasing environmental concern in freshwater worldwide. Our field investigations coupled with laboratory incubations demonstrated that the microbial degradation potential of 17ß-estradiol (E2) with estrone as the intermediate was primarily driven by increased dissolved organic matter (DOM) in the water column of a cyanobacterial bloom. To explain the intrinsic contribution of cyanobacterial-derived DOM (C-DOM) to estrogen biodegradation, a combination of methods including bioassay, ultrahigh-resolution mass spectrometry, and microbial ecology were applied. The results showed that preferential assimilation of highly biodegradable structures, including protein-, carbohydrate-, and unsaturated hydrocarbon-like molecules sustained bacterial growth, selected for more diverse microbes, and resulted in greater estrogen biodegradation compared to less biodegradable molecules (lignin- and tannin-like molecules). The biodegradability of C-DOM decreased from 78% to 1%, whereas the E2 biodegradation rate decreased dramatically at first, then increased with the accumulation of recalcitrant, bio-produced lipid-like molecules in C-DOM. This change was linked to alternative substrate-induced selection of the bacterial community under highly refractory conditions, as suggested by the greater biomass-normalized E2 biodegradation rate after a 24-h lag phase. In addition to the increased frequency of potential degraders, such as Sphingobacterium, the network analysis revealed that C-DOM molecules distributed in high H/C (protein- and lipid-like molecules) were the main drivers structuring the bacterial community, inducing strong deterministic selection of the community assemblage and upregulating the metabolic capacity for contaminants. These findings provide strong evidence that estrogen biodegradation in eutrophic water may be facilitated by cyanobacterial blooms and provide a theoretical basis for ecological remediation of estrogen pollution.


Assuntos
Cianobactérias , Lagos , Estrogênios , Estrona , Água
8.
Int J Pharm ; 608: 121091, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34555477

RESUMO

Cancer vaccines targeting tumor specific neoantigens derived from nonsynonymous mutations of tumor cells have emerged as an effective approach to induce antitumor T cells responses for personalized cancer immunotherapy. Despite the enormous potential of synthetic peptides as a common modality for neoantigen vaccines, their practical efficacy was limited due to their relatively low immunogenicity. Herein, we modify neoantigen peptide (Adpgk) derived from MC-38 colon carcinoma by supplementing ten consecutive positively-charged lysines (10 K-Adpgk) to obtain cationic polypeptide. And then we made them self-assemble with toll-like receptor 9 (TLR-9) agonist CpG oligodeoxynucleotides (CpG ODN) adjuvant directly forming antigen/adjuvant integrated nanocomplexes (PCNPs) through electrostatic interaction for potent tumor immunotherapy. The optimal formed PCNPs were around 175 nm with uniform size distribution and could maintain stability in physiological saline solution. CpG ODN and 10 K-Adpgk in the formed PCNPs could be effectively uptake by dendritic cells (DCs) and stimulate the maturation of DCs as well as improving the efficiency of antigen cross-presentation efficiency in vitro. Furthermore, the PCNPs vaccine could markedly improve neoantigen and adjuvant co-delivery efficiency to lymphoid organs and activate cytotoxic T cells. In addition, vaccination with PCNPs could not only offer prophylactic to protect mice from challenged MC-38 colorectal tumors, but also achieve a better anti-tumor effect in an established colorectal tumor model, and significantly prolong the survival rate of tumor-bearing mice. Therefore, this work provided a versatile but effective method for neoantigen peptide and CpG ODN co-assembly vaccine platform for efficient colorectal cancer immunotherapy.


Assuntos
Vacinas Anticâncer , Neoplasias Colorretais , Imunoterapia , Receptor Toll-Like 9/agonistas , Adjuvantes Imunológicos , Animais , Neoplasias Colorretais/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Oligodesoxirribonucleotídeos , Peptídeos
9.
Huan Jing Ke Xue ; 42(7): 3263-3271, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212652

RESUMO

Increased loads of biogenic and terrestrial natural organic matter into freshwater lakes are projected to be a major consequence of global climate change and cyanobacterial blooms. In this study, the effects of phytoplankton-derived organic matter (POM) and terrestrial humic acid (HA) on the activity, composition, and function of the microbial community in Lake Taihu sediments were investigated. Fluorescent spectra demonstrated that POM with high chemodiversity was composed of labile protein-like components (50%) and recalcitrant humic-like components (50%), while humic-like substances accounted for 97% of HA. Over two-month periods, the organic carbon mineralization in sediments was enhanced owing to increasing NOM concentrations; however, the carbon consumption in POM-amended sediments was significantly higher than that in sediments amended with the same concentrations of HA. Analysis of extracellular polymeric substances indicated that NOM input improved the microbial secretion of proteins and polysaccharides, increasing the aggregation and stability of the microbial community. The amendment of POM also stimulated the activity of organic matter metabolic enzymes, promoting microbial activity. Moreover, 16S rRNA gene sequencing suggested that the mineralization of NOM (especially POM) increased the diversity of the microbial community, favored the survival of Proteobacteria and Bacteroidetes, and upregulated the function genes of organic matter metabolism. These results suggest that the composition and function of microbial community in sediments were associated with the origin, composition, and concentration of NOM input.


Assuntos
Cianobactérias , Microbiota , Sedimentos Geológicos , Substâncias Húmicas/análise , Lagos , RNA Ribossômico 16S
10.
Water Res ; 184: 116153, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32726734

RESUMO

Climate change and increasing eutrophication are expected to increase the release of autochthonous organic matter (OM) to sediments, where most contaminants are transformed or mineralized in freshwater lakes. This study sought to evaluate how cyanobacteria- and macrophyte-derived OM (COM and MOM) affected the microbial attenuation of 17α-ethinylestradiol (EE2) in the sediment from eutrophic Lake Taihu in China. In two months of water-sediment microcosm experiments, the input of COM and MOM both promoted EE2 degradation more strongly than humic acids, and the degradation efficiency was significantly and positively correlated with the cometabolism of increasing organic carbon in sediments (P < 0.001). The enhanced degradation was explained by responses of indigenous bacterial community to OM amendment as a priming effect. The immediate breakdown of biodegradable components such as proteinaceous substances in COM and MOM remarkably augmented the metabolic activity of bacteria in terms of the stimulated activity of extracellular enzymes including fluorescein diacetate and dehydrogenase, as well as the elevated production of proteins and polysaccharides in extracellular polymeric substances. In the meantime, the bacterial community composition was reshaped toward a more eutrophic state, leading to the clear upregulation of metabolic function genes of organic carbon and xenobiotics. Correlation-based network analysis further determined the strong facilitative coordination between the community members and the compositional variability of OM in the cometabolism. These results suggest that cyanobacterial blooms-dominated zones are potential hotspot areas for steroid estrogen attenuation, a finding of significance for the control and management of complex pollution in freshwater lakes.


Assuntos
Cianobactérias , Lagos , China , Eutrofização , Sedimentos Geológicos , Água
11.
Ying Yong Sheng Tai Xue Bao ; 23(2): 426-32, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22586968

RESUMO

To clarify the leading climate factors affecting the distribution of single cropping rice planting region in China at national and annual temporal scales and to reveal the potential distribution and climatic suitability divisions of this planting region in China could not only provide scientific basis for optimizing the allocation of single cropping rice production, modifying planting pattern, and introducing fine varieties, but also ensure the food security of China. In this paper, the potential climate factors affecting the single cropping rice distribution in China at regional and annual scales were selected from related literatures, and the single cropping rice geographic information from the national agro-meteorological observation stations of China Meteorological Administration (CMA), together with the maximum entropy model (MaxEnt) and spatial analyst function of Arc-GIS software, were adopted to clarify the leading climate factors affecting the potential distribution of single cropping rice planting region in China, and to construct a model about the relationships between the potential distribution of the planting region and the climate. The results showed that annual precipitation, moisture index, and days of not less than 18 degrees C stably were the leading climate factors affecting the potential distribution of single cropping rice planting region in China, with their cumulative contribution rate reached 94.5% of all candidate climate factors. The model constructed in this paper could well simulate the potential distribution of single cropping rice planting region in China. According to the appearance frequency, the low, medium and high climatic suitability divisions of single cropping rice planting region in China were clarified, and the climate characteristics of the planting region in each climatic suitability division were analyzed.


Assuntos
Clima , Modelos Teóricos , Oryza/crescimento & desenvolvimento , China , Sistemas de Informação Geográfica , Conceitos Meteorológicos , Chuva
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