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1.
Hypoxic–ischemic encephalopathy (HIE) is a devastating neonatal brain condition caused by lack of oxygen and limited blood flow. Environmental enrichment (EE) is a classic paradigm with a complex stimulation of physical, cognitive, and social components. EE can exert neuroplasticity and neuroprotective effects in immature brains. However, the exact mechanism of EE on the chronic condition of HIE remains unclear. HIE was induced by a permanent ligation of the right carotid artery, followed by an 8% O2 hypoxic condition for 1 h. At 6 weeks of age, HIE mice were randomly assigned to either standard cages or EE cages. In the behavioral assessments, EE mice showed significantly improved motor performances in rotarod tests, ladder walking tests, and hanging wire tests, compared with HIE control mice. EE mice also significantly enhanced cognitive performances in Y-maze tests. Particularly, EE mice showed a significant increase in Cav 2.1 (P/Q type) and presynaptic proteins by molecular assessments, and a significant increase of Cav 2.1 in histological assessments of the cerebral cortex and hippocampus. These results indicate that EE can upregulate the expression of the Cav 2.1 channel and presynaptic proteins related to the synaptic vesicle cycle and neurotransmitter release, which may be responsible for motor and cognitive improvements in HIE.  相似文献   
2.
Jeong  Ji-Seong  Song  Min-Ho  Lee  Sang-Ho  Kim  Mihye  Baek  Nakhoon  Yoo  Kwan-Hee 《The Journal of supercomputing》2019,75(8):4505-4518
The Journal of Supercomputing - This paper presents a web-based three-dimensional (3D) navigation system for a spinal disease ontology using a 3D virtual human spine. The 3D navigation system...  相似文献   
3.
In this paper, we propose a novel formulation extending convolutional neural networks (CNN) to arbitrary two-dimensional manifolds using orthogonal basis functions called Zernike polynomials. In many areas, geometric features play a key role in understanding scientific trends and phenomena, where accurate numerical quantification of geometric features is critical. Recently, CNNs have demonstrated a substantial improvement in extracting and codifying geometric features. However, the progress is mostly centred around computer vision and its applications where an inherent grid-like data representation is naturally present. In contrast, many geometry processing problems deal with curved surfaces and the application of CNNs is not trivial due to the lack of canonical grid-like representation, the absence of globally consistent orientation and the incompatible local discretizations. In this paper, we show that the Zernike polynomials allow rigourous yet practical mathematical generalization of CNNs to arbitrary surfaces. We prove that the convolution of two functions can be represented as a simple dot product between Zernike coefficients and the rotation of a convolution kernel is essentially a set of 2 × 2 rotation matrices applied to the coefficients. The key contribution of this work is in such a computationally efficient but rigorous generalization of the major CNN building blocks.  相似文献   
4.
Baek  Ji Min  Ji  Sang Hoon  Koo  Ja Choon 《Microsystem Technologies》2020,26(11):3389-3394
Microsystem Technologies - Rotating components are one of the most important machine parts used in many industrial applications. Rotating machine commonly used in homes has a washing machine, which...  相似文献   
5.
In this paper, we present a performance analysis of large-scale multi-input multi-output (MIMO) systems for wireless backhaul networks. We focus on fully connected N nodes in a wireless meshed and multi-hop network topology. We also consider a large number of antennas at both the receiver and transmitter. We investigate the transmission schemes to support fully connected N nodes for half-duplex and full-duplex transmission, analyze the achievable ergodic sum rate among N nodes, and propose a closed-form expression of the achievable ergodic sum rate for each scheme. Furthermore, we present numerical evaluation results and compare the resuts with closed-form expressions.  相似文献   
6.
Journal of Mechanical Science and Technology - The threaded fasteners are typical machine components in tightening of the machine parts and structures. In addition, as threaded fasteners are easy...  相似文献   
7.
Two donor–acceptor-type alternating copolymers consisting of 2,1,3-benzoselenadiazole and carbazole derivatives with thiophene or selenophene π-bridges were synthesized by Suzuki cross-coupling polymerization, and their optical, electrochemical, and photovoltaic properties were compared. The selenophene π-bridged copolymer (PCz-DSeBSe) exhibited a smaller band-gap (1.82 eV) than the thiophene-bridged polymer (PCz-DTBSe; 1.89 eV). PCz-DSeBSe also showed a deeper highest occupied molecular orbital energy level (−5.36 eV) than PCz-DTBSe (−5.20 eV). Moreover, the PCz-DSeBSe thin film showed higher crystallinity and hole mobility than the PCz-DTBSe thin film. Organic photovoltaic devices were fabricated using the polymers as the donors and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor. The device using PCz-DSeBSe showed a higher open circuit voltage (Voc), short circuit current density (Jsc), and power conversion efficiency (PCE) than that using PCz-DTBSe. The fabricated indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/PCz-DSeBSe:PC71BM/LiF/Al device showed the maximum PCE of 2.88% with a Jsc of 7.87 mA/cm2, an Voc of 0.80 V, and a fill factor of 0.50 under AM 1.5G irradiation (100 mW/cm2).  相似文献   
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9.
Stems of Machilus japonica were extracted with 80% aqueous methanol (MeOH) and the concentrated extract was successively extracted with ethyl acetate (EtOAc), normal butanol (n-BuOH), and water. Six flavonoids were isolated from the EtOAc fraction: (+)-taxifolin, afzelin, (−)-epicatechin, 5,3''-di-O-methyl-(−)-epicatechin, 5,7,3''-tri-O-methyl-(−)-epicatechin, and 5,7-di-O-methyl-3'',4''-methylenedioxyflavan-3-ol. The chemical structures were identified using spectroscopic data including NMR, mass spectrometry and infrared spectroscopy. This is the first report of isolation of these six compounds from M. japonica. The compounds were evaluated for their diphenyl picryl hydrazinyl scavenging activity and inhibitory effects on low-density lipoprotein oxidation. Compounds 1 and 3–6 exhibited DPPH antioxidant activity equivalent with that of ascorbic acid, with half maximal inhibitory concentration (IC50) values of 0.16, 0.21, 0.17, 0.15 and 0.07 mM, respectively. The activity of compound 1 was similar to the positive control butylated hydroxytoluene, which had an IC50 value of 1.9 µM, while compounds 3 and 5 showed little activity. Compounds 1, 3, and 5 exhibited LDL antioxidant activity with IC50 values of 2.8, 7.1, and 4.6 µM, respectively.  相似文献   
10.
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