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1.
Molecules ; 29(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38731589

RESUMO

Multiscale nano/micro-structured surfaces with superhydrophobicity are abundantly observed in nature such as lotus leaves, rose petals and butterfly wings, where microstructures typically reinforce mechanical stability, while nanostructures predominantly govern wettability. To emulate such hierarchical structures in nature, various methods have been widely applied in the past few decades to the manufacture of multiscale structures which can be applied to functionalities ranging from anti-icing and water-oil separation to self-cleaning. In this review, we highlight recent advances in nano/micro-structured superhydrophobic surfaces, with particular focus on non-metallic materials as they are widely used in daily life due to their lightweight, abrasion resistance and ease of processing properties. This review is organized into three sections. First, fabrication methods of multiscale hierarchical structures are introduced with their strengths and weaknesses. Second, four main application areas of anti-icing, water-oil separation, anti-fog and self-cleaning are overviewed by assessing how and why multiscale structures need to be incorporated to carry out their performances. Finally, future directions and challenges for nano/micro-structured surfaces are presented.

2.
Front Nutr ; 10: 1155436, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006935

RESUMO

Introduction: Metabolic syndrome (MetS) is considered as a complex, intertwined multiple risk factors that directly increase the risk of various metabolic diseases, especially cardiovascular atherosclerotic diseases and diabetes mellitus type 2. While lifestyle changes, including dietary intervention are effective in mitigating or preventing MetS, there are no specific therapies against MetS. Typical western diets comprise of high saturated fatty acid, cholesterol, and simple sugar; consequently their consumption may increase the potential pathological developmental risk of MetS. Partial replacement of dietary fatty acids with polyunsaturated fatty acids (PUFAs) is widely recommended measure to manage MetS-related disorders. Methods: In the present study, we used rat model to investigate the role of n-3 PUFA enriched beef tallows (BT) on MetS and tunicamycin (TM)-induced endoplasmic reticulum (ER) stress, by partially replacing dietary fat (lard) with equal amounts of two different BTs; regular BT or n-3 PUFA-enriched BT. The experimental rats were randomly assigned to three different dietary groups (n = 16 per group): (1) high-fat and high-cholesterol diet (HFCD); (2) HFCD partially replaced with regular BT (HFCD + BT1); (3) HFCD partially replaced with n-3 enhanced BT (w/w) (HFCD + BT2). After 10 weeks of dietary intervention, each experimental rodent was intraperitoneally injected with either phosphate-buffered saline or 1 mg/kg body weight of TM. Results: HFCD + BT2 showed improved dyslipidemia before TM injection, and increased serum high-density lipoprotein cholesterol (HDL-C) levels after TM injection. BT replacement groups had significantly reduced hepatic triglyceride (TG) levels, and decreased total cholesterol (TC) and TG levels in epididymal adipose tissue (EAT). Furthermore, BT replacement remarkably attenuated TM-induced unfolded protein responses (UPRs) in liver, showing reduced ER stress, with BT2 being more effective in the EAT. Discussion: Therefore, our findings suggest that partially replacing dietary fats with n-3 PUFA to lower the ratio of n-6/n-3 PUFAs is beneficial in preventing pathological features of MetS by alleviating HFCD- and/or TM-induced dyslipidemia and ER stress.

3.
Sensors (Basel) ; 21(21)2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34770704

RESUMO

The aim of this paper is to distinguish the vehicle detection and count the class number in each classification from the inputs. We proposed the use of Fuzzy Guided Scale Choice (FGSC)-based SSD deep neural network architecture for vehicle detection and class counting with parameter optimization. The 'FGSC' blocks are integrated into the convolutional layers of the model, which emphasize essential features while ignoring less important ones that are not significant for the operation. We created the passing detection lines and class counting windows and connected them with the proposed FGSC-SSD deep neural network model. The 'FGSC' blocks in the convolution layer emphasize essential features and find out unnecessary features by using the scale choice method at the training stage and eliminate that significant speedup of the model. In addition, FGSC blocks avoided many unusable parameters in the saturation interval and improved the performance efficiency. In addition, the Fuzzy Sigmoid Function (FSF) increases the activation interval through fuzzy logic. While performing operations, the FGSC-SSD model reduces the computational complexity of convolutional layers and their parameters. As a result, the model tested Frames Per Second (FPS) on edge artificial intelligence (AI) and reached a real-time processing speed of 38.4 and an accuracy rate of more than 94%. Therefore, this work might be considered an improvement to the traffic monitoring approach by using edge AI applications.


Assuntos
Inteligência Artificial , Sulfadiazina de Prata , Algoritmos , Lógica Fuzzy , Redes Neurais de Computação
4.
PLoS One ; 10(7): e0132300, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26161964

RESUMO

Recently, some studies have applied the graph theory in brain network analysis in Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI). However, relatively little research has specifically explored the properties of the metabolic network in apolipoprotein E (APOE) ε4 allele carriers. In our study, all the subjects, including ADs, MCIs and NCs (normal controls) were divided into 165 APOE ε4 carriers and 165 APOE ε4 noncarriers. To establish the metabolic network for all brain regions except the cerebellum, cerebral glucose metabolism data obtained from FDG-PET (18F-fluorodeoxyglucose positron emission tomography) were segmented into 90 areas with automated anatomical labeling (AAL) template. Then, the properties of the networks were computed to explore the between-group differences. Our results suggested that both APOE ε4 carriers and noncarriers showed the small-world properties. Besides, compared with APOE ε4 noncarriers, the carriers showed a lower clustering coefficient. In addition, significant changes in 6 hub brain regions were found in between-group nodal centrality. Namely, compared with APOE ε4 noncarriers, significant decreases of the nodal centrality were found in left insula, right insula, right anterior cingulate, right paracingulate gyri, left cuneus, as well as significant increases in left paracentral lobule and left heschl gyrus in APOE ε4 carriers. Increased local short distance interregional correlations and disrupted long distance interregional correlations were found, which may support the point that the APOE ε4 carriers were more similar with AD or MCI in FDG uptake. In summary, the organization of metabolic network in APOE ε4 carriers indicated a less optimal pattern and APOE ε4 might be a risk factor for AD.


Assuntos
Alelos , Apolipoproteína E4/genética , Fluordesoxiglucose F18 , Redes e Vias Metabólicas , Tomografia por Emissão de Pósitrons , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Mapeamento Encefálico , Análise por Conglomerados , Feminino , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade
5.
Brain Inform ; 2(1): 45-52, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27747502

RESUMO

Brain networks can be divided into two categories: structural and functional networks. Many studies of neuroscience have reported that the complex brain networks are characterized by small-world or scale-free properties. The identification of nodes is the key factor in studying the properties of networks on the macro-, micro- or mesoscale in both structural and functional networks. In the study of brain networks, nodes are always determined by atlases. Therefore, the selection of atlases is critical, and appropriate atlases are helpful to combine the analyses of structural and functional networks. Currently, some problems still exist in the establishment or usage of atlases, which are often caused by the segmentation or the parcellation of the brain. We suggest that quantification of brain networks might be affected by the selection of atlases to a large extent. In the process of building atlases, the influences of single subjects and groups should be balanced. In this article, we focused on the effects of atlases on the analysis of brain networks and the improved divisions based on the tractography or connectivity in the parcellation of atlases.

6.
J Biomed Opt ; 19(3): 36003, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24599085

RESUMO

Photoacoustic microscopy (PAM) is becoming a vital tool for various biomedical studies, including functional and molecular imaging of cancer. However, due to the use of a focused ultrasonic transducer for photoacoustic detection, the image quality of conventional PAM degrades rapidly away from the ultrasonic focal zone. To improve the image quality of PAM for out-of-focus regions, we have developed compressed sensing based virtual-detector photoacoustic microscopy (CS-PAM). Through phantom and in vivo experiments, it has been demonstrated that CS-PAM can effectively extend the depth of focus of PAM, and thus may greatly expand its potential biomedical applications.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos , Técnicas Fotoacústicas/métodos , Animais , Camundongos , Camundongos Nus , Imagens de Fantasmas
7.
PLoS One ; 9(3): e92463, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24651256

RESUMO

Photoacoustic imaging is an emerging technology that can provide anatomic, functional, and molecular information about biological tissue. Intravascular spectroscopic and molecular photoacoustic imaging can potentially improve the identification of atherosclerotic plaque composition, the detection of inflammation, and ultimately the risk stratification of atherosclerosis. In this study, a first-of-its-kind intravascular optical-resolution photoacoustic tomography (OR-PAT) system with a 1.1 mm diameter catheter is developed, offering optical-diffraction limited transverse resolution as fine as 19.6 µm, ∼ 10-fold finer than that of conventional intravascular photoacoustic and ultrasonic imaging. To offer complementary imaging information and depth, the system also acquires co-registered intravascular ultrasound images in parallel. Imaging of an iliac stent and a lipid phantom shows that the high resolution and contrast of OR-PAT can enable improved stent implantation guidance and lipid identification. In the future, these capabilities may ultimately improve the diagnosis and interventional treatment of vulnerable atherosclerotic plaques, which are prone to cause thrombotic complications such as myocardial infarction and stroke.


Assuntos
Técnicas Fotoacústicas/métodos , Tomografia Óptica/métodos , Dispositivos de Acesso Vascular , Aterosclerose/diagnóstico , Doenças Cardiovasculares/diagnóstico , Humanos , Técnicas Fotoacústicas/instrumentação , Tomografia Óptica/instrumentação , Ultrassonografia de Intervenção/métodos
8.
Biomaterials ; 34(21): 5236-43, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23602365

RESUMO

Theranostic agents are attracting a great deal of attention in personalized medicine. Here, we developed a protein-based, facile method for fabrication of nanosized, reduced graphene oxide (nano-rGO) with high stability and low cytotoxicity. We constructed highly integrated photoacoustic/ultrasonic dual-modality imaging and photothermal therapy platforms, and further demonstrated that the prepared nano-rGO can be used as ready-to-use theranostic agents for both photoacoustic imaging and photothermal therapy without further surface modification. Intravenous administration of nano-rGO in tumor-bearing mice showed rapid and significant photoacoustic signal enhancement in the tumor region, indicating its excellence for passive targeting and photoacoustic imaging. Meanwhile, using a continuous-wave near-infrared laser, cancer cells in vivo were efficiently ablated, due to the photothermal effect of nano-rGO. The results suggest that the nano-rGO with protein-assisted fabrication was well suited for photoacoustic imaging and photothermal therapy of tumor, which is promising for theranostic nanomedicine.


Assuntos
Grafite/química , Hipertermia Induzida/métodos , Nanopartículas/química , Óxidos/química , Técnicas Fotoacústicas/métodos , Fototerapia/métodos , Soroalbumina Bovina/metabolismo , Animais , Bovinos , Sobrevivência Celular , Feminino , Humanos , Raios Infravermelhos , Células MCF-7 , Camundongos , Camundongos Nus , Nanopartículas/ultraestrutura , Especificidade de Órgãos , Oxirredução , Espectroscopia Fotoeletrônica , Espectrofotometria Ultravioleta , Espectroscopia de Luz Próxima ao Infravermelho , Testes de Toxicidade , Ultrassom , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 19(4): 579-82, 2002 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-12561352

RESUMO

In this paper, the structure parameters and the equations to calculate these parameters are presented for the model design of the artificial bio-valve on the basis of heart anatomy, shell theory and the optimal flow of heart valve. No-root bio-valve is designed and manufactured according to the above theoies and technology. Its perfect property has been confirmed by measurement in vitro and clinical application in vivo.


Assuntos
Desenho Assistido por Computador , Próteses Valvulares Cardíacas , Algoritmos , Análise Numérica Assistida por Computador , Desenho de Prótese/métodos
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