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Intervertebral disc (IVD) diseases are common spinal disorders that cause neck or back pain in the presence or absence of an underlying neurological disorder. IVD diseases develop on the basis of degeneration, and there are no established treatments for degeneration. IVD diseases may therefore represent a candidate for the application of regenerative medicine, potentially employing normal human dermal fibroblasts (NHDFs) induced to differentiate into nucleus pulposus (NP) cells. Here, we used a three-dimensional culture system to demonstrate that ectopic expression of MYC, KLF4, NOTO, SOX5, SOX6, and SOX9 in NHDFs generated NP-like cells, detected using Safranin-O staining. Quantitative PCR, microarray analysis, and fluorescence-activated cell sorting revealed that the induced NP cells exhibited a fully differentiated phenotype. These findings may significantly contribute to the development of effective strategies for treating IVD diseases.  相似文献   
73.
Flexible multifunctional electronic devices are of high interest for a wide range of applications including thermal therapy and respiratory devices in medical treatment, safety equipment, and structural health monitoring systems. This paper reports a scalable and efficient strategy of manufacturing a polyacrylonitrile‐carbon nanotube‐polyacrylonitrile (PAN‐CNT‐PAN) robust flexible platform for multifunctional electronic devices including flexible heaters, temperature sensors, and flexible thermal flow sensors. The key advantages of this platform include low cost, porosity, mechanical robustness, and electrical stability under mechanical bending, enabling the development of fast‐response flexible heaters with a response time of ≈1.5 s and relaxation time of ≈1.7 s. The temperature‐sensing functionality is also investigated with a range of temperature coefficient of resistances from ?650 to ?900 ppm K?1. A flexible hot‐film sensing concept is successfully demonstrated using PAN‐CNT‐PAN with a high sensitivity of 340 mV (m s?1)?1. The sensitivity enhancement of 50% W?1 is also observed with increasing supply power. The low cost, porosity, versatile, and robust properties of the proposed platform will enable the development of multifunctional electronic devices for numerous applications such as flexible thermal management, temperature stabilization in industrial processing, temperature sensing, and flexible/wearable devices for human healthcare applications.  相似文献   
74.
Vu  Thang X.  Trinh  Anh Vu  Chatzinotas  Symeon  Tran  Xuan Nam 《Wireless Networks》2020,26(6):4403-4410

Edge caching has received much attention as a promising technique to overcome the stringent latency and data-hungry challenges in the future generation wireless networks. Meanwhile, full-duplex (FD) transmission can potentially double the spectral efficiency by allowing a node to receive and transmit at the same frequency band simultaneously. In this paper, we investigate the delivery time performance of a cache-aided FD system, in which an edge node, operates in FD mode, serves users via wireless channels and is equipped with a cache memory. Firstly, we derive a closed-form expression for the average delivery time by taking into account the uncertainties of both backhaul and access wireless channels. The derived analysis allows the examination of the impact of key parameters, e.g., cache size and transmit power. Secondly, a power optimization problem is formulated to minimize the average delivery time. To deal with the non-convexity of the formulated problem, we propose an iterative optimization algorithm based on the bisection method. Finally, numerical results are presented to demonstrate the effectiveness of the proposed algorithm. A significant delivery time reduction is achieved by the proposed optimization compared to the FD reference and half-duplex counterpart.

  相似文献   
75.
BACKGROUND/AIMS: Gallbladder mucus itself has been recognized to play an important role in gallstone development. Despite the diverse mechanisms of stone induction and the differences in stone composition, there is a quantitative increase in the epithelial mucus production period before stone formation. As brown pigment stones are found frequently in gallstone disease, we conducted a study on gallbladders with brown pigment stones or combination stones with a brown periphery to evaluate the mucin content in the gallbladder epithelium in comparison to gallbladders with cholesterol stones and those without stones. METHODS: Gallbladder specimens were fixed in 10% formalin immediately after cholecystectomy and then embedded in paraffin. The specimens were sectioned for periodic acid-Schiff-alcian blue (PAS-AB, pH 2.5) double stain to evaluate the intra-epithelial mucin content. The PAS-AB index was calculated as a proportion of the PAS-AB-positive mucin area to the total epithelial area, using a computerized image analyzer. RESULTS: Evaluation of the PAS-AB index on the lining epithelia of gallbladders showed that it was 32.43 +/- 9.96% in gallbladders with brown stones, which is significantly (p < 0.001) higher than in gallbladders with cholesterol stones (15.63 +/- 6. 75%) and gallbladders without stones (9.55 +/- 4.77%). CONCLUSION: The results show that gallbladders with brown stones contain more abundant mucin than gallbladders with cholesterol stones or those without stones. They also suggest that the gallbladder epithelium per se might play a more important role in stone formation in those with brown stones than in those with cholesterol stones.  相似文献   
76.
In the present work, we report first results about a technology using a conjugated copolymer poly(5-hydroxy-1,4-naphthoquinone-co-5-hydroxy-2-carboxyethyl-1,4-naphthoquinone) acting both as immobilizing and transducing element for reagentless immunosensor, and its application for the detection of HPV infection. It was shown that the reagentless immunosensor was able to detect the interaction between antigenic peptide L1 from HPV-16 major capsid protein, a dominant epitope involved in viral infection as well as in prophylactic vaccine, and the relevant antibody.  相似文献   
77.
A significant discharge capacity increase (larger than 3 times) for the gas-diffusion-electrode (GDE) used in Li-air cells was demonstrated through modification of the carbon surface with long-chain hydrophobic molecules. The capacity loss of the Li-air activated carbon cathode was found to be caused by the formation of undesired surface passivation. The mechanism of such passivation was identified as the formation of dense Li oxide films directly on the surface of the carbon during the oxygen reduction reaction. Such dense layers of Li oxide are here identified as the root cause of the undesired passivation, which blocks electrochemical reactions, increases the impedance and drops the discharge voltage rapidly. This investigation reveals that the capacity for the gas-diffusion-electrode can be substantially increased, if the activated carbon is modified by attaching long-chain hydrophobic molecules onto the surface. The carbon surface modification significantly delays the formation of the dense Li oxide layers. Therefore, the discharge capacity for the GDE is substantially increased.  相似文献   
78.
In this paper, a zinc oxide (ZnO) nanotube, fabricated by the hydrothermal growth method on triple-junction (T-J) solar cell devices to enhance efficiency, is investigated. Compared to those of bare T-J solar cells (without antireflection (AR) coating) and solar cells with Si3N4 AR coatings, the experimental results show that the T-J solar cells, which use a ZnO nanotube as an AR coating, have the lowest reflectance in the short wavelength spectrum. The ZnO nanotube has the lowest light reflection among all experimental samples, especially in the range of 350 to 500 nm from ultraviolet (UV) to visible light. It was found that a ZnO nanotube can enhance the conversion efficiency by 4.9%, compared with a conventional T-J solar cell. The Si3N4 AR coatings also enhance the conversion efficiency by 3.2%.The results show that a cell with ZnO nanotube coating could greatly improve solar cell performances.  相似文献   
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