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91.
92.
Da-Jeong Chang Seung-Hun Oh Nayeon Lee Chunggab Choi Iksoo Jeon Hyun Sook Kim Dong Ah Shin Seo Eun Lee Daehong Kim Jihwan Song 《Experimental & molecular medicine》2013,45(11):e53
The transplantation of neural precursor cells (NPCs) is known to be a promising approach to ameliorating behavioral deficits after stroke in a rodent model of middle cerebral artery occlusion (MCAo). Previous studies have shown that transplanted NPCs migrate toward the infarct region, survive and differentiate into mature neurons to some extent. However, the spatiotemporal dynamics of NPC migration following transplantation into stroke animals have yet to be elucidated. In this study, we investigated the fates of human embryonic stem cell (hESC)-derived NPCs (ENStem-A) for 8 weeks following transplantation into the side contralateral to the infarct region using 7.0T animal magnetic resonance imaging (MRI). T2- and T2*-weighted MRI analyses indicated that the migrating cells were clearly detectable at the infarct boundary zone by 1 week, and the intensity of the MRI signals robustly increased within 4 weeks after transplantation. Afterwards, the signals were slightly increased or unchanged. At 8 weeks, we performed Prussian blue staining and immunohistochemical staining using human-specific markers, and found that high percentages of transplanted cells migrated to the infarct boundary. Most of these cells were CXCR4-positive. We also observed that the migrating cells expressed markers for various stages of neural differentiation, including Nestin, Tuj1, NeuN, TH, DARPP-32 and SV38, indicating that the transplanted cells may partially contribute to the reconstruction of the damaged neural tissues after stroke. Interestingly, we found that the extent of gliosis (glial fibrillary acidic protein-positive cells) and apoptosis (TUNEL-positive cells) were significantly decreased in the cell-transplanted group, suggesting that hESC-NPCs have a positive role in reducing glia scar formation and cell death after stroke. No tumors formed in our study. We also performed various behavioral tests, including rotarod, stepping and modified neurological severity score tests, and found that the transplanted animals exhibited significant improvements in sensorimotor functions during the 8 weeks after transplantation. Taken together, these results strongly suggest that hESC-NPCs have the capacity to migrate to the infarct region, form neural tissues efficiently and contribute to behavioral recovery in a rodent model of ischemic stroke. 相似文献
93.
Dr. Javeed Mahmood Seok‐Jin Kim Hyuk‐Jun Noh Dr. Sun‐Min Jung Ishfaq Ahmad Dr. Feng Li Jeong‐Min Seo Prof. Jong‐Beom Baek 《Angewandte Chemie (International ed. in English)》2018,57(13):3415-3420
A three‐dimensional (3D) cage‐like organic network (3D‐CON) structure synthesized by the straightforward condensation of building blocks designed with gas adsorption properties is presented. The 3D‐CON can be prepared using an easy but powerful route, which is essential for commercial scale‐up. The resulting fused aromatic 3D‐CON exhibited a high Brunauer–Emmett–Teller (BET) specific surface area of up to 2247 m2 g?1. More importantly, the 3D‐CON displayed outstanding low pressure hydrogen (H2, 2.64 wt %, 1.0 bar and 77 K), methane (CH4, 2.4 wt %, 1.0 bar and 273 K), and carbon dioxide (CO2, 26.7 wt %, 1.0 bar and 273 K) uptake with a high isosteric heat of adsorption (H2, 8.10 kJ mol?1; CH4, 18.72 kJ mol?1; CO2, 31.87 kJ mol?1). These values are among the best reported for organic networks with high thermal stability (ca. 600 °C). 相似文献
94.
Lithium‐Ion Endohedral Fullerene (Li+@C60) Dopants in Stable Perovskite Solar Cells Induce Instant Doping and Anti‐Oxidation 下载免费PDF全文
Dr. Il Jeon Dr. Hiroshi Ueno Seungju Seo Dr. Kerttu Aitola Ryosuke Nishikubo Prof. Akinori Saeki Dr. Hiroshi Okada Prof. Gerrit Boschloo Prof. Shigeo Maruyama Prof. Yutaka Matsuo 《Angewandte Chemie (International ed. in English)》2018,57(17):4607-4611
Herein, we report use of [Li+@C60]TFSI? as a dopant for spiro‐MeOTAD in lead halide perovskite solar cells. This approach gave an air stability nearly 10‐fold that of conventional devices using Li+TFSI?. Such high stability is attributed to the hydrophobic nature of [Li+@C60]TFSI? repelling moisture and absorbing intruding oxygen, thereby protecting the perovskite device from degradation. Furthermore, [Li+@C60]TFSI? could oxidize spiro‐MeOTAD without the need for oxygen. The encapsulated devices exhibited outstanding air stability for more than 1000 h while illuminated under ambient conditions. 相似文献
95.
Hyun Ook Seo Myung‐Geun Jeong Kwang‐Dae Kim Dae Han Kim Young Dok Kim Dong Chan Lim 《Surface and interface analysis : SIA》2014,46(8):544-549
Degradation behaviors of poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) layers on NiO in the presence of H2O at ambient pressure and dark conditions were studied using X‐ray photoelectron spectroscopy (XPS). Upon H2O exposure at 120 °C, partial oxidation of P3HT together with molecular water incorporation, but with the maintained local ring‐structure, were deduced by XPS. Valence band spectra of XPS evidenced that the partial oxidation of P3HT local structure could alter π‐conjugation systems of P3HT layers, forming additional electronic states close to its original highest occupied molecular orbital. For comparison, P3HT surface was also exposed to O2, and no change in the S 2p and C 1s spectra was found by O2 exposure at 120 °C, implying that H2O plays a major role at the initial stage of P3HT oxidation. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
96.
97.
A. Akindinov A. Alici P. Antonioli S. Arcelli M. Basile F. Bellini D. Caffarri G. Cara Romeo L. Cifarelli F. Cindolo A. De Caro D. De Gruttola S. De Pasquale K. Doroud M. Fusco Girard B. Guerzoni D. Hatzifotiadou W. W. Jung D. W. Kim J. S. Kim S. Kiselev G. Laurenti K. Lee S. C. Lee D. Malkevich A. Margotti R. Nania A. Nedosekin F. Noferini P. Pagano A. Pesci O. Pinazza R. Preghenella M. Ryabinin E. Scapparone G. Scioli J. Seo A. Silenzi K. Voloshin M. C. S. Williams C. Zampolli A. Zichichi 《The European Physical Journal C - Particles and Fields》2010,68(3-4):601-607
The Time-Of-Flight detector (TOF) of the ALICE experiment at the CERN LHC is based on Multi-gap Resistive Plate Chambers (MRPCs). The TOF detector consists of 152928 readout channels covering a total area of 141 m2. In this paper the results of the calibration with cosmic-ray data collected during 2009 are presented. 相似文献
98.
99.
We investigated the high-energy electronic structure of a 5d perovskite SrHfO3 by using optical spectroscopy and O 1s x-ray absorption spectroscopy. From the combined spectra the values of electronic structure parameters are estimated properly. In particular, the crystal field splitting energy, which is closely associated with the p–d hybridization strength, is as high as ~5 eV, and the Sr 4d bands appear to be strongly mixed with the Hf 5d bands. These findings are discussed in relation to a possible ferroelectric instability in SrHfO3, and are compared with electronic properties of similar compounds, 3d SrTiO3 and 4d SrZrO3. 相似文献
100.
Thermal, structural and optical properties of Nd3+ ions in tellurite glass (TeO2-ZnO-Na2O-Li2O-Nb2O5) have been investigated. Differential thermal analysis revealed reasonably good forming tendency of the glass composition. FTIR spectra were used to analyze the functional groups present in the glass. Judd-Ofelt intensity parameters were derived from the absorption spectrum and used to calculate the radiative lifetime, branching ratio and stimulated emission cross-section of the 4F3/2→4I9/2, 11/2, 13/2 transitions. The quantum efficiency of the 4F3/2 level is comparable as well as higher than the typical value of the other tellurite based glasses. The decay from the 4F3/2 level is found to be single exponential for different concentrations of Nd3+ ions with a shortening of lifetime with increasing concentration. The experimental values of branching ratio and saturation intensity of 4F3/2→4I11/2 transition indicate the favourable lasing action with low threshold power. 相似文献