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Suk-Young Song Soonil Pyo Sungchul Choi Hee Sang Oh Jung Hwa Seo Ji Hea Yu Ahreum Baek Yoon-Kyum Shin Hoo Young Lee Ja Young Choi Sung-Rae Cho 《International journal of molecular sciences》2021,22(7)
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
3.
Food Science and Biotechnology - MV was reported to have beneficial effects in ameliorating insulin resistance in db/db mice, but the intrinsic mechanisms for glucose homeostasis are unclear. This... 相似文献
4.
This paper addresses the problem of visual simultaneous localization and mapping (SLAM) in an unstructured seabed environment that can be applied to an unmanned underwater vehicle equipped with a single monocular camera as the main measurement sensor. Monocular vision is regarded as an efficient sensing option in the context of SLAM, however it poses a variety of challenges when the relative motion is determined by matching a pair of images in the case of in-water visual SLAM. Among the various challenges, this research focuses on the problem of loop-closure which is one of the most important issues in SLAM. This study proposes a robust loop-closure algorithm in order to improve operational performance in terms of both navigation and mapping by efficiently reconstructing image matching constraints. To demonstrate and evaluate the effectiveness of the proposed loop-closure method, experimental datasets obtained in underwater environments are used, and the validity of the algorithm is confirmed by a series of comparative results. 相似文献
5.
The novel Fe/Nb co-doped SrCo1 ? 2x(Fe,Nb)xO3 ? δ (x = 0.05, 0.10) perovskite oxides were synthesized by the solid-state method. Structural and chemical stability of the SrCo1 ? 2x(Fe,Nb)xO3 ? δ (x = 0.05, 0.10) oxides were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and X-ray diffraction (XRD). The results demonstrated that the structural and chemical stability of the Fe/Nb co-doped SrCo1 ? 2x(Fe,Nb)xO3 ? δ (x = 0.05, 0.10) is improved significantly. The oxygen sorption properties of the SrCo1 ? 2x(Fe,Nb)xO3 ? δ (x = 0.05, 0.10) oxides were investigated between 300–900 °C in air, and the high oxygen sorption capacity of 11.5 and 10.3 mL O2 (STP)/g oxide, respectively, are obtained. 相似文献
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Sung Gyu Pyo 《Metals and Materials International》2010,16(2):293-297
When a dip test in buffered oxide etching chemicals is combined with narrow contact pattern, the test can be used as a simple barrier evaluation method, especially for predicting of IPVD (Ionized Physical Vapor Deposition) extendibility. In spite of the excellent coverage of IPVD TaNx films the structural defect at the corner of the pattern could be the root cause of device degradation. The use of extremely thin IPVD TaNx film of around 20 Å was limited by the contact of less than 0.2 μm and an AR (Aspect Ratio) value greater than 4:1. 相似文献
8.
A new chelating fabrics are synthesized by radiation induced grafting of acrylonitrile (AN) onto polypropylene nonwoven fabrics (PP fabrics) and subsequent conversion of cyano to an imine by reaction with ethylene diimine (EDA). Influence of various parameters such as initial concentration, pH and adsorption time on the adsorption amount for palladium ions was investigated. It was found that adsorbent achieved excellent adsorption performance in palladium ion removal in the pH range of 1.88–5.70. The adsorption amount of ions increased with shaking time and initial concentration of palladium ions. The grafted and aminated fabrics were characterized by FT‐IR, TGA and SEM. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
9.
Min Jung Kang Youn Hee Kim Gun Pyo Park Mi Sun Han Woo Nyon Kim Sang Do Park 《Journal of Materials Science》2010,45(19):5412-5419
The effects of liquid-type nucleating silane additives on the cell structure, mechanical strength, and thermal insulating
properties of the polyisocyanurate (PIR) foams have been studied. The PIR foams synthesized with hexamethyldisilazane (HMDS)
as a silane additive showed the smaller average cell size and lower thermal conductivity than those of the PIR foams prepared
with the hexamethyldisiloxane, dimethoxydimethylsilane, and hexadecyltrimethoxysilane. When HMDS was added, average cell size
of the PIR foam was becoming smaller due to lower surface tension of the polyol solution, thereby the nucleation rate and
number of bubbles produced were increased and then the cell size becomes smaller. The additives likely act as nucleating agents
during the formation of PIR foams. The smaller cell size appears to be one of the major reasons for the improvement of thermal
insulation properties and mechanical properties of the PIR foams. From the results of cell size, thermal conductivity, and
mechanical strength of the PIR foams, it is suggested that the HMDS may be the efficient liquid-type additive for the reduction
of cell size and improvement of the thermal insulation property of the PIR foams. 相似文献
10.
An aerosol dynamics equation for the below-cloud scavenging process considering phoretic and electric charging effects in addition to the conventional mechanisms (the Brownian diffusion, interception, and impaction) is developed by using the moment method. Then, the dynamics of particle size distribution by the below-cloud scavenging process is calculated by using the developed equation and verified with the measurement data. The calculated particle size distribution changes are quite small compared to the measured changes. The calculated removal rate is smaller by 10?2–10?3 than the measured data when only the conventional mechanisms are considered. With the extended mechanisms, the scavenging coefficient increases upto 20 times, mainly for the particle size range of 0.1 μm<dp<3.0 μm. However, the difference between the calculated and measured scavenging coefficient is still large, especially, for dp<0.1 μm. Other possible scavenging mechanisms that might affect the below-cloud scavenging process such as coagulation and condensational growth of hygroscopic particles, turbulence, and updraft into cloud are discussed. It is recommended that further studies on wet scavenging process are needed. 相似文献