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11.
Focal adhesions are polyproteins linked to extracellular matrix and cytoskeleton, which play an important role
in the process of transforming force signals into intracellular chemical signals and subsequently triggering related
physiological or pathological reactions. The cytoskeleton is a network of protein fibers in the cytoplasm, which is
composed of microfilaments, microtubules, intermediate filaments, and cross-linked proteins. It is a very important
structure for cells to maintain their basic morphology. This review summarizes the process of fluid shear stress
transduction mediated by focal adhesion and the key role of the cytoskeleton in this process, which focuses on the
focal adhesion and cytoskeleton systems. The important proteins involved in signal transduction in focal adhesion are
introduced emphatically. The relationship between focal adhesion and mechanical transduction pathways are
discussed. In this review, we discuss the relationship between fluid shear stress and associated diseases such as
atherosclerosis, as well as its role in clinical research and drug development. 相似文献
12.
为了探究浮选机孔径大小对煤泥浮选试验的影响,通过煤泥颗粒与气泡的碰撞概率及粘附作用,适当调节叶轮转速,求得不同条件下精煤产率、精煤灰分、尾煤灰分以及可燃体回收率等值,验证浮选机孔径变化的影响效应。结果表明,增大浮选机进气管孔径,矿浆内大直径的气泡较多,与粗煤泥的携载作用增大,与细粒煤泥碰撞概率降低,部分矿粒无法粘附;减小浮选机进气管的孔径,其作用与上述情况恰好相反。两种条件下选取适当且相同的叶轮转速,试验后可以看出,气泡孔径的大小对粗细煤泥作用影响不同,但究其综合因素较复杂,增加或减小气泡尺寸对试验结果无较大影响。 相似文献
13.
Soumya Ghosh Chowdhury Jagannath Chanda Sreedip Ghosh Koushik Banerjee Shib Shankar Banerjee Amit Das Prasenjit Ghosh Sanjay Kr. Bhattacharyya Rabindra Mukhopadhyay 《Polymer Engineering and Science》2020,60(8):1973-1983
Proficiency on underlying mechanism of rubber-metal adhesion has been increased significantly in the last few decades. Researchers have investigated the effect of various ingredients, such as hexamethoxymethyl melamine, resorcinol, cobalt stearate, and silica, on rubber-metal interface. The role of each ingredient on rubber-metal interfacial adhesion is still a subject of scrutiny. In this article, a typical belt skim compound of truck radial tire is selected and the effect of each adhesive ingredient on adhesion strength is explored. Out of these ingredients, the effect of cobalt stearate is found noteworthy. It has improved adhesion strength by 12% (without aging) and by 11% (humid-aged), respectively, over control compound. For detailed understanding of the effect of cobalt stearate on adhesion, scanning electron microscopy and energy dispersive spectroscopy are utilized to ascertain the rubber coverage and distribution of elements. X-ray photoelectron spectroscopy results helped us to understand the impact of CuXS layer depth on rubber-metal adhesion. The depth profile of the CuXS layer was found to be one of the dominant factors of rubber-metal adhesion retention. Thus, this study has made an attempt to find the impact of different adhesive ingredients on the formation of CuXS layer depth at rubber-metal interface and establish a correlation with adhesion strength simultaneously. 相似文献
14.
Md Arifuzzaman Uneb Gazder Muhammad Saiful Islam 《Journal of Adhesion Science and Technology》2020,34(10):1100-1114
AbstractThe expected longer service life of modified asphalt can be jeopardized by different environmental factors, such as moisture, oxidation, etc. which affect the desired properties by altering the adhesive property. An insight into knowledge of the adhesive property of the asphalt can help in providing more durable asphalt pavement. The study attempted to develop different models of adhesive properties of polymers and carbon nanotubes (CNTs) modified asphalt binders. The polymer-CNT modified asphalt is processed to prepare different types of samples, by simulating the damage due to moisture and oxidization, following the corresponding standard method. An Atomic Force Microscopy (AFM) was employed to assess the nanoscale adhesion force of the tested samples following the existing functional group in asphalt. Finally, the study has developed Radial Basis Function Neural Network (RBFNN) as a function of different parameters including; asphalt chemistry (i.e. AFM tip type and constant), type and percentages of polymers and CNTs and different environmental exposures (oxidation, moisture, etc.) to predict the nano adhesion force of asphalt. It is observed that the adhesive property of the Styrene–Butadiene modified asphalt is more consistent compared to the Styrene–Butadiene–Styrene modified asphalt, while the presence of Single-Wall Nanotubes (SWNT) is observed to affect the adhesive properties of asphalt significantly as compared to Multi-Wall Nanotubes (MWNT). The higher accuracy level of RBFNN model also indicates that the functional group (tip-type) adding with the percentages and types of polymers and CNTs significantly affect the adhesive properties of asphalt. 相似文献
15.
《Ceramics International》2020,46(5):5649-5657
To establish the relationship between wettability and structure with the change in SAW flux composition, the contact angle measurement study was performed at 1700 K. For MgO–TiO2–SiO2 and Al2O3–MgO–SiO2 flux system the wetting behaviour was studied by evaluating the contact angle as well as surface tension properties. Sessile drop method was used to determine the wetting properties of SAW fluxes. Twenty-one SAW fluxes were designed & developed by applying mixture design approach of design of experiments. Chemical, phase and structural properties of SAW fluxes were measured using modern techniques such as X-ray fluorescence (XRF), X-ray diffraction (XRD) & Fourier Transform Infra-red spectroscopy (FTIR). As per the calculated contact angle value, different surface tension values for MgO–TiO2–SiO2 and Al2O3–MgO–SiO2 flux system was calculated using Young's & Boni's equations. Using Dupre's equation the adhesion energy for twenty-one basic fluxes was also calculated. Measured contact angle value increased with increase in the TiO2/MgO & TiO2/Al2O3 flux ratio. Lower contact angle gives higher wettability between the flux and the heating substrate. With increase of TiO2/SiO2 ratio up to 1.5 to 2.0 the calculated surface tension value is decreasing while after that it is increased with increase in TiO2/SiO2 ratio. 相似文献
16.
17.
Dynamic pull-in/pull-off forces were quantitatively measured using an AFM colloidal probe technique. Two spherical colloids made of silicon dioxide (SiO2) and gold (Au) that were attached to an AFM cantilever were approached to and retracted from a silicon wafer specimen, where the speed of tip approaching/retracting (i.e., vertical dynamics) and specimen sliding (i.e., horizontal dynamics) was controlled. First, when the vertical dynamics of colloidal tip was applied on the stationary silicon wafer specimen, it was observed that the slower tip approaching showed higher pull-in force, while the pull-off force was dependent on both the applied force and the retracting speed. For the two colloidal tips, it was found that the higher applied force and the faster tip retraction led to the higher pull-off force. Next, under the constant speed of tip approach and retraction, horizontal dynamics was applied to the silicon wafer specimen. It was observed that the horizontal motion of the specimen made the pull-off force lower, which could be attributed to the breakage of adhesive asperity junctions at the interface. The pull-off force was further decreased at faster horizontal motion of the specimen due to the longer sliding distance. Therefore, from the systematic experiments of dynamic adhesion measurement, it could be known that if a micro/nano-system is under dynamic surface interaction, its adhesive force cannot be fully described by a conventional quasi-static adhesion model but it should include the effects of applied system dynamics in both normal and tangential directions. 相似文献
18.
RAFAEL SCAF DE MOLON MARTA MARIA ALVES PEREIRA ERICA DORIGATTI DE AVILA 《Biocell》2022,46(5):1151-1156
It has been recognized that physical and chemical properties of biomaterial surfaces mediate the quality of extracellular matrix (ECM) that may affect cell behaviors. In nature, ECM is a heterogeneous three-dimensional superstructure formed by three major components, glycosaminoglycan, glycoconjugate, and protein, that anchors cellular compartments in tissues and regulates the function and the behavior of cells. Changes in the biointerface alter the quality of ECM and morphology through cell surface receptors, which, in turn, enable it to trigger specific cell signaling and different cellular responses. In fact, a number of strategies have been used to improve the functionality of surfaces and direct cell behavior through precisely designed environments. Herein, we aimed to discuss, through a science-based viewpoint, the biomaterial surface features on cell behavior and analyze the impact of cell physical modification on dental implant development. 相似文献
19.
J. Schaaf 《Journal of Adhesion Science and Technology》2018,32(19):2111-2127
The strong ice bonding to solid surfaces makes deicing such surfaces a challenging task. In this study, a heat flux will be induced into the interlayer of the ice and in this case aluminum. With a high heat flux it is possible to obtain a small liquid layer between the ice and the aluminum. In metallic materials the heat flux can be induced with an electromagnetic field via induction heating. The thickness of the heated metal layer depends on the frequency applied for the induction heating. High frequencies result in very thin layers of metal heated and hence represent an energy efficient method for de-icing the metal surface. The reduction of the energy consumption for deicing is the main goal. One application is the ice removal in ice slurry generators in this study. Compared to ice removal (scraped surface ice slurry generators) induction heating deicing offers energy and maintenance saving potential. 相似文献
20.
A simple interface fracture test for ceramic environmental barrier coatings (EBCs) on ceramic matrix composites (CMCs) was developed. A variation on the asymmetric double cantilever beam (ADCB) test was proposed so that the interface toughness could be measured in a small specimen of simple shape without applying interlaminar loading to the CMC substrate. The proposed test was applied to an EBC consisting of a mullite layer and Si bond coat on a monolithic SiC substrate. A pre-crack was introduced by pop-in cracking, and then a notch overlapping the pre-crack was machined. The pre-crack was opened by inserting a wedge into the notch. From the critical notch opening displacement the crack starts to propagate, interface toughness is calculated. The measured interface toughness was 4.1?J/m2. Finally, the application range of the test was discussed and suggestions were made for introduction of the notch and pre-crack. 相似文献