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排序方式: 共有334条查询结果,搜索用时 31 毫秒
41.
Simultaneous production of mevinolins (natural statins) and ubiquinones (coenzyme Qs; CoQ9 and CoQ10) were identified and determined in solid substrates fermented (SSF) with Monascus pilosus K-1140. The highest co-production of mevinolins (2.31±0.11 mg/g) and ubiquinones (0.24±0.02 mg/g) was obtained in a mixed
grains substrate (rice:sorghum:barley:buckwheat:soybean; 1:1:1:1:1; w/w/w/w/w). The optimal conditions for mixed grains in
the SSF were initial moisture content of 50% and initial substrate pH of 6. The total production of CoQs was increased by
32% with the addition of red paprika. Mevinolinic acid (hypocholesterolemic agent) was the main component contributing 81.3
to 91.5% of total mevinolins in the fermented substrates. The results indicate that mixed grain fermented with M. pilosus may be used as a new nutraceuticals with anti-atherosclerotic function without statin-induced CoQ10 deficiency. 相似文献
42.
A tall building reacts sensitively to winds because the wind force increases according to the height and shape of the building. Various shapes of tall buildings and their aerodynamic characteristics have been studied extensively. For structural design and occupant comfort, the dynamic displacement of a tall building must be maintained within the criteria for acceptable levels of wind‐induced motion. An aerodynamically appropriate building shape needs to be selected at the design stage of a tall building. In this study, wind‐induced vibration responses were investigated, according to the criteria for maximum acceptable displacement and acceleration. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
43.
Jeong‐Seok Kim Wonkyu Choi Gil‐Young Choi Cheol‐Sig Pyo Jong‐Suk Chae 《ETRI Journal》2008,30(4):600-602
A very small patch‐type RFID tag antenna (UHF band) using ceramic material mountable on metallic surfaces is presented. The size of the proposed tag is 25 mm×25 mm×3 mm. The impedance of the antenna can be easily matched to the tag chip impedance by adjusting the size of the shorting plate of the patch and the size of the feeding loop. The measured maximum reading distance of the tag at 910 MHz was 5 m when it was mounted on a 400 mm × 400 mm metallic surface. The proposed design is verified by simulation and measurements which show good agreement. 相似文献
44.
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
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47.
Hyune‐Jea Lee Robert C. Roberts Do Jin Im Se‐Jun Yim Heejin Kim Ji Tae Kim Dong‐Pyo Kim 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(50)
High‐resolution 3D‐printed stainless steel metal microreactors (3D‐PMRs) with different cross‐sectional geometry are fabricated to control ultrafast intramolecular rearrangement reactions in a comparative manner. The 3D‐PMR with circular channel demonstrates the improved controllability in rapid Fries‐type rearrangement reactions, because of the superior mixing efficiency to rectangular cross‐section channels (250 µm × 125 µm) which is confirmed based on the computational flow dynamics simulation. Even in case of very rapid intramolecular rearrangement of sterically small acetyl group occurring in 333 µs of reaction time, the desired intermolecular reaction can outpace to the undesired intramolecular rearrangement using 3D‐PMR to result in high conversion and yield. 相似文献
48.
Jaeyong Lee Soonjae Pyo Dae‐Sung Kwon Eunhwan Jo Wondo Kim Jongbaeg Kim 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(12)
Although there have been remarkable improvements in stretchable strain sensors, the development of strain sensors with scalable fabrication techniques and which both high sensitivity and stretchability simultaneously is still challenging. In this work, a stretchable strain sensor based on overlapped carbon nanotube (CNT) bundles coupled with a silicone elastomer is presented. The strain sensor with overlapped CNTs is prepared by synthesizing line‐patterned vertically aligned CNT bundles and rolling and transferring them to the silicone elastomer. With the sliding and disconnection of the overlapped CNTs, the strain sensor performs excellently with a broad sensing range (≥145% strain), ultrahigh sensitivity (gauge factor of 42 300 at a strain of 125–145%), high repeatability, and durability. The performance of the sensor is also tunable by controlling the overlapped area of CNT bundles. Detailed mechanisms of the sensor and its applications in human motion detection are also further investigated. With the novel structure and mechanism, the sensor can detect a wide range of strains with high sensitivity, demonstrating the potential for numerous applications including wearable healthcare devices. 相似文献
49.
Hyun Kyu Shin Si Woon Lee Goo Pyo Hong Lee Sael Sang Hyo Lee Ha Young Kim 《计算机、材料和连续体(英文)》2021,66(3):2493-2507
The demand for defect diagnoses is gradually gaining ground owing to the growing necessity to implement safe inspection methods to ensure the durability and quality of structures. However, conventional manpower-based inspection methods not only incur considerable cost and time, but also cause frequent disputes regarding defects owing to poor inspections. Therefore, the demand for an effective and efficient defect-diagnosis model for concrete structures is imminent, as the reduction in maintenance costs is significant from a long-term perspective. Thus, this paper proposes a deep learning-based image object-identification method to detect the defects of paint peeling, leakage peeling, and leakage traces that mostly occur in underground parking lots made of concrete structures. The deep learning-based object-detection method can replace conventional visual inspection methods. A faster region-based convolutional neural network (R-CNN) model was used with a training dataset of 6,281 images that utilized a region proposal network to objectively localize the regions of interest and detect the surface defects. The defects were classified according to their type, and the learning of each exclusive model was ensured through test sets obtained from real underground parking lots. As a result, average precision scores of 37.76%, 36.42%, and 61.29% were obtained for paint peeling, leakage peeling, and leakage trace defects, respectively. Thus, this study verified the performance of the faster RCNN-based defect-detection algorithm along with its applicability to underground parking lots. 相似文献
50.
Yoo Byoung-Wook Kim Bom Joshi Pankaj Kwon Sung-Ok Kim YeonJin Oh Jung-Sook Kim Jeongseon Oh Se-Young Lim Ji-Ae Choi Byung-Sun Kim Yu-Mi Eom Sang-Yong Hong Young-Seob Sohn Seok-Joon Park Kyung-Su Pyo Heesoo Kim Ho Ha Mina Park Jung-Duck Kwon Ho-Jang Lee Sang-Ah 《Food science and biotechnology》2018,27(4):1227-1237
Food Science and Biotechnology - This study was aimed to examine the association the blood/urinary concentration of toxic metal (Hg, Pb, and Cd) with children’s dietary patterns. This... 相似文献