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1.
ACS Biomater Sci Eng ; 9(11): 6084-6093, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37909852

RESUMO

Degradability is vital for bone filling and plays an important role in bone regeneration. Evidence indicates that apatite-based calcium phosphate cement (ACPC) is a prospective biomaterial for bone repair with enhanced osteogenesis. However, poor degradability restricts their clinical application. In this study, MgZnCa-doped ACPC (MgZnCa/ACPC) composites were fabricated by adding 3 (wt) % amorphous MgZnCa powder in the solid phase of ACPC to enhance the biodegradation and bioactivity of the apatite ACPC. The chemical and the physical properties of the MgZnCa/ACPC composite were investigated and compared with the ACPC composite. The results showed that the incorporation of MgZnCa improved both the degradability and the compressive strength of the ACPC composite. X-ray diffraction and Fourier transform infrared spectrometry analysis suggested significant changes in the microstructures of the composites due to the incorporation and the anodic dissolution of MgZnCa alloy. These findings indicate that the MgZnCa/ACPC composite is capable of facilitating bone repair and regeneration by endowing favorable degradation property.


Assuntos
Ligas , Apatitas , Apatitas/metabolismo , Ligas/química , Estudos Prospectivos , Teste de Materiais , Fosfatos de Cálcio/química , Cimentos Ósseos/química
2.
Molecules ; 28(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37513377

RESUMO

Intelligentization of materials and structures is an important trend. Herein, the stimuli-responsive 4D aerogel is used as a smart substrate for rapid reduction in tetracycline (TC) pollution, in which this smart stimuli-responsive substrate is designated as P4D. Its fourth dimension originates from stimuli-responsive characteristics with time evolution. Meanwhile, the covalent organic frameworks (COFs) composite is constructed by BiPO4 and triazine-based sp2 carbon-conjugated g-C18N3-COF (COF-1), which is another key aspect of COF-1/BiPO4@P4D for rapid photocatalytic degradation regarding TC pollution. This emerging smart structure of COFs@P4D can fix programmable temporary state and recover permanent state under thermal or water stimulus without any complicated equipment. Its performance can be tailored by structure, composition, and function. Compared with traditional powder-form photocatalysts, this stimuli-responsive structure provides attractive advantages, such as high permeable framework, self-adaptivity, flexibly customized functional groups, and fast reduction in TC pollution. The predictable development of COFs@P4D could draw much attention for various promising applications in pollution treatment and sensors.

3.
PLoS One ; 18(4): e0282357, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37023085

RESUMO

Due to a series of societal factors, management of small rural water resources projects in China experience management problems. Based on the management mode of small water resources projects in three representative regions of Guangdong Province, the improved TOPSIS model is applied to evaluate the performance of management mode of small water resources projects through the combination with entropy weight method. Compared with the traditional TOPSIS model concerning the evaluation object of this paper, the evaluation value formulas of optimal and worst solutions of TOPSIS method are improved. The evaluation index system takes into account the coverage, hierarchy and systematization of indicators, and maintains a management mode with high environmental adaptability, so that the continuous operation of management mode can guaranteed. The results show that the management mode of water user association is most suitable for the development of small water resources projects in Guangdong Province.


Assuntos
Recursos Hídricos , China , Entropia
4.
IEEE Trans Neural Netw Learn Syst ; 34(8): 3897-3911, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34714755

RESUMO

With the development of remote sensing technology, panchromatic images (PANs) and multispectral images (MSs) can be easily obtained. PAN has higher spatial resolution, while MS has more spectral information. So how to use the two kinds of images' characteristics to design a network has become a hot research field. In this article, a multi-scale progressive collaborative attention network (MPCA-Net) is proposed for PAN and MS's fusion classification. Compared to the traditional multi-scale convolution operations, we adopt an adaptive dilation rate selection strategy (ADR-SS) to adaptively select the dilation rate to deal with the problem of category area's excessive scale differences. For the traditional pixel-by-pixel sliding window sampling strategy, the patches which are generated by adjacent pixels but belonging to different categories contain a considerable overlap of information. So we change original sampling strategy and propose a center pixel migration (CPM) strategy. It migrates the center pixel to the most similar position of the neighborhood information for classification, which reduces network confusion and increases its stability. Moreover, due to the different spatial and spectral characteristics of PAN and MS, the same network structure for the two branches ignores their respective advantages. For a certain branch, as the network deepens, characteristic has different representations in different stages, so using the same module in multiple feature extraction stages is inappropriate. Thus we carefully design different modules for each feature extraction stage of the two branches. Between the two branches, because the strong mapping methods of directly cascading their features are too rough, we design collaborative progressive fusion modules to eliminate the differences. The experimental results verify that our proposed method can achieve competitive performance.

5.
BMC Genomics ; 23(1): 26, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991478

RESUMO

BACKGROUND: Valgus-varus deformity (VVD) is a lateral or middle deviation of the tibiotarsus or tarsometatarsus, which is associated with compromised growth, worse bone quality and abnormal changes in serum indicators in broilers. To investigate the genetic basis of VVD, a genome wide association study (GWAS) was performed to identify candidate genes and pathways that are responsible for VVD leg disease, serum indicators and growth performance in broilers. RESULTS: In total, VVD phenotype, seven serum indicators and three growth traits were measured for 126 VVD broilers (case group) and 122 sound broilers (control group) based on a high throughput genome wide genotyping-by-sequencing (GBS) method. After quality control 233 samples (113 sound broilers and 120 VVD birds) and 256,599 single nucleotide polymorphisms (SNPs) markers were used for further analysis. As a result, a total of 5 SNPs were detected suggestively significantly associated with VVD and 70 candidate genes were identified that included or adjacent to these significant SNPs. In addition, 43 SNPs located on Chr24 (0.22 Mb - 1.79 Mb) were genome-wide significantly associated with serum alkaline phosphatase (ALP) and 38 candidate genes were identified. Functional enrichment analysis showed that these genes are involved in two Gene Ontology (GO) terms related to bone development (cartilage development and cartilage condensation) and two pathways related to skeletal development (Toll-like receptor signaling pathway and p53 signaling pathway). BARX2 (BARX homeobox 2) and Panx3 (Pannexin 3) related to skeleton diseases and bone quality were obtained according to functional analysis. According to the integration of GWAS with transcriptome analysis, HYLS1 (HYLS1 centriolar and ciliogenesis associated) was an important susceptibility gene. CONCLUSIONS: The results provide some reference for understanding the relationship between metabolic mechanism of ALP and pathogenesis of VVD, which will provide a theoretical basis for disease-resistant breeding of chicken leg soundness.


Assuntos
Galinhas , Estudo de Associação Genômica Ampla , Animais , Galinhas/genética , Perfilação da Expressão Gênica , Fenótipo , Polimorfismo de Nucleotídeo Único
6.
IEEE Trans Cybern ; 52(11): 12571-12582, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34166211

RESUMO

In this article, an adaptive neural safe tracking control scheme is studied for a class of uncertain nonlinear systems with output constraints and unknown external disturbances. To allow the output to stay in the desired output constraints, a boundary protection approach is developed and utilized in the output constrained problem. Since the generated output constraint trajectory is piecewise differentiable, a dynamic surface method is utilized to handle it. For the purpose of approximating the system uncertainties, a radial basis function neural network (RBFNN) is adopted. Under the output of the RBFNN, the disturbance observer technology is employed to estimate the unknown compound disturbances of the system. Finally, the Lyapunov function method is utilized to analyze the convergence of the tracking error. Taking a two-link manipulator system, as an example, the simulation results are presented to illustrate the feasibility of the proposed control scheme.


Assuntos
Redes Neurais de Computação , Dinâmica não Linear , Simulação por Computador , Retroalimentação , Projetos de Pesquisa
7.
Bioresour Technol ; 338: 125486, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273626

RESUMO

The integration of anaerobic digestion (AD) and pyrolysis (Py) could be a solution to economically utilize the organic fraction of municipal solid waste (OFMSW). However, it is not clear whether the environmental impact of the integrated pathway always outperforms the two single technologies. In this study, two integrated pathways (AD-Py, Py-AD) were compared with single AD and Py from the life cycle environmental impacts point of view. The results indicate that the environmental impacts of the four pathways are heavily dependent on their energy inputs and outputs. AD-Py is more environmentally friendly (-11.53 of total environmental impact /kg OFMSW) than single AD or Py. Py-AD exhibites the heaviest environmental burden (2.75 of total environmental impact /kg OFMSW) in all pathways. Therefore, AD-Py can be the top priority of treating OFMSW among the four pathways from the environmental viewpoint. This work could provide a theoretical support for the utilization of OFMSW.


Assuntos
Eliminação de Resíduos , Resíduos Sólidos , Anaerobiose , Animais , Reatores Biológicos , Estágios do Ciclo de Vida , Metano , Pirólise , Resíduos Sólidos/análise
8.
Chempluschem ; 86(3): 406-417, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33645899

RESUMO

Water is a significant and abundant resource as well as a pure natural energy source. Many researchers have been reported on humidity-responsive actuators that mimick the humidity responsive behavior that widely exists in nature. Benefiting from advantages such as hydrophilicity, high electrical conductivity, and good dispersibility, MXenes (Ti3 C2 Tx ) show promising performance when applied to humidity-responsive actuators. This Minireview describes the preparation methods and structural characteristics of MXenes, and the mechanism of humidity-responsive actuators. Recent important advances of MXene materials in actuators are objectively reviewed and evaluated, and existing issues are discussed. In addition, the development of these systems is outlined from the aspects of MXene preparation, structure control, design and assembly, and applications, and provides new ideas and guidance for the development of the next generation of high-performance MXene-based humidity-responsive actuators.

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