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Coexistence of Th1/Th2 and Thl7/Treg imbalances in patients with allergic asthma 被引量:122
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作者 SHI Yu-heng SHI Guo-chao +7 位作者 WAN Huan-ying JIANG Li-hua AI xiang-yan ZHU Hai-xing TANG Wei MA Jia-yun JIN Xiao-yan ZHANG Bo-ying 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第13期1951-1956,共6页
Background Recent recognition is that Th2 response is insufficient to fully explain the aetiology of asthma. Other CD4^+ T cells subsets might play a role in asthma. We investigated the relative abundance and activit... Background Recent recognition is that Th2 response is insufficient to fully explain the aetiology of asthma. Other CD4^+ T cells subsets might play a role in asthma. We investigated the relative abundance and activities of Thl, Th2, Th17 and CD4^+CD25^+ Treg cells in patients with allergic asthma. Methods Twenty-two patients with mild asthma, 17 patients with moderate to severe asthma and 20 healthy donors were enrolled. All patients were allergic to house dust mites. Plasma total IgE, pulmonary function and Asthma Control Questionnaire were assessed. The proportions of peripheral blood Thl, Th2, Th17 and CD4^+CD25^+ Treg cells were determined by flow cytometry. The expression of cytokines in plasma and Jn the culture supernatant of peripheral blood mononuclear cells was determined by enzyme linked, immunosorbent assay. Results The frequency of blood Th2 cells and IL-4 levels in plasma and culture supernatant of peripheral blood mononuclear cells were increased in all patients with allergic asthma. The frequency of Th17 cells and the plasma and culture supernatant levels of IL-17 were increased, whereas the frequency of CD4^+CD25^+ Treg cells and plasma IL-10 levels were decreased in patients with moderate to severe asthma. Dermatophagoides pteronyssinus specific IgE levels were positively correlated with the percentage of blood Th2 cells and plasma IL-4 levels. Forced expiratory volume in the first second was negatively correlated with the frequency of Th17 cells and plasma IL-17 levels, and positively correlated with the frequency of Treg cells. However, mean Asthma Control Questionnaire scores were positively correlated with the frequency of Th17 cells and plasma IL-17 levels, and negatively correlated with the frequency of Treg cells. Conclusions Imbalances in Thl/Th2 and Th17/Treg were found in patients with allergic asthma. Furthermore, elevated Th17 cell responses, the absence of Tregs and an imbalance in Th17/Treg levels were associated with moderate to severe asthma. 展开更多
关键词 allergic asthma Thl cells Th2 cells Thl 7 cells regulatory T cells
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高通量测序方法研究传统四川泡菜母水中微生物群落的动态变化 被引量:46
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作者 李恒 陈功 +5 位作者 伍亚龙 邓维琴 张伟 朱翔 王勇 张其圣 《食品科学》 EI CAS CSCD 北大核心 2018年第24期131-138,共8页
为探明传统四川泡菜母水中的微生物群落及其变化规律,构建传统四川泡菜发酵模型,运用高通量测序方法对不同发酵阶段(20代发酵)泡菜母水微生物群落组成和多样性进行分析。泡菜母水中的细菌群落主要包括7个门,其中厚壁菌门(Firmicutes)和... 为探明传统四川泡菜母水中的微生物群落及其变化规律,构建传统四川泡菜发酵模型,运用高通量测序方法对不同发酵阶段(20代发酵)泡菜母水微生物群落组成和多样性进行分析。泡菜母水中的细菌群落主要包括7个门,其中厚壁菌门(Firmicutes)和变形菌门(Proteobacteria)分别占94.64%和2.73%,为优势菌门;真菌群落主要包括3个门和1个未分类种群,其中子囊菌门(Ascomycota)占99.93%,为优势菌门。泡菜母水中含量在0.1%以上的细菌属有7个,主要包括乳杆菌属(Lactobacillus)、拉乌尔菌属(Raoultella)、柠檬酸杆菌属(Citrobacter)、乳球菌属(Lactococcus)等;泡菜母水中的真菌属主要是Kazachstania,含量超过99%。通过分析不同发酵阶段泡菜母水中的微生物群落组成和多样性,结果表明随着发酵代数的增加,泡菜母水中的细菌与真菌多样性呈下降趋势,微生物群落构成趋于稳定:Lactobacillus是达到稳态的泡菜母水中的主要细菌属,Kazachstania是达到稳态的泡菜母水中的主要真菌属。 展开更多
关键词 四川泡菜 泡菜母水 高通量测序 微生物多样性 不同代数
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Protective role of berberine on ulcerative colitis through modulating enteric glial cells-intestinal epithelial cells-immune cells interactions 被引量:44
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作者 heng Li Chen Fan +6 位作者 Huimin Lu Chunlan Feng Peilan He Xiaoqian Yang Caigui xiang Jianping Zuo Wei Tang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2020年第3期447-461,共15页
Ulcerative colitis(UC)manifests as an etiologically complicated and relapsing gastrointestinal disease.The enteric nervous system(ENS)plays a pivotal role in rectifying and orchestrating the inflammatory responses in ... Ulcerative colitis(UC)manifests as an etiologically complicated and relapsing gastrointestinal disease.The enteric nervous system(ENS)plays a pivotal role in rectifying and orchestrating the inflammatory responses in gut tract.Berberine,an isoquinoline alkaloid,is known as its antiinflammatory and therapeutic effects in experimental colitis.However,little research focused on its regulatory function on ENS.Therefore,we set out to explore the pathological role of neurogenic inflammation in UC and the modulating effects of berberine on neuro-immune interactions.Functional defects of enteric glial cells(EGCs),with decreased glial fibrillary acidic protein(GFAP)and increased substance P expression,were observed in DSS-induced murine UC.Administration of berberine can obviously ameliorate the disease severity and restore the mucosal barrier homeostasis of UC,closely accompanying by maintaining the residence of EGCs and attenuating inflammatory infiltrations and immune cells overactivation.In vitro,berberine showed direct protective effects on monoculture of EGCs,bone marrowderived dendritic cells(BMDCs),T cells,and intestinal epithelial cells(IECs)in the simulated inflammatory conditions.Furthermore,berberine could modulate gut EGCs-IECs-immune cell interactions in the co-culture systems.In summary,our study indicated the EGCs-IECs-immune cell interactions might function as a crucial paradigm in mucosal inflammation and provided an infusive mechanism of berberine in regulating enteric neurogenic inflammation. 展开更多
关键词 ULCERATIVE COLITIS BERBERINE MUCOSAL inflammation ENTERIC GLIAL cells ENTERIC nervous system
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:40
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作者 xiang-Qun Cui Yong-heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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High entropy defective fluorite structured rare-earth niobates and tantalates for thermal barrier applications 被引量:36
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作者 Zifan ZHAO heng CHEN +6 位作者 Huimin xiang Fu-Zhi DAI Xiaohui WANG Wei XU Kuang SUN Zhjjian PENG Yanchun ZHOU 《Journal of Advanced Ceramics》 SCIE CSCD 2020年第3期303-311,共9页
Rare-earth tantalates and niobates(REjTaO7 and REjNbO7)have been considered as promising candidate thermal barrier coating(TBC)materials in next generation gas-turbine engines due to their ultra-low thermal conductivi... Rare-earth tantalates and niobates(REjTaO7 and REjNbO7)have been considered as promising candidate thermal barrier coating(TBC)materials in next generation gas-turbine engines due to their ultra-low thermal conductivity and better thermal stability than yttria-stabilized zirconia(YSZ).However,the low Vickers hardness and toughness are the main shortcomings of RE;TaO-and REjNbOr that limit their applications as TBC materials.To increase the hardness,high entropy(Yu3Ybu3Er/3)sTaOr,(Y13YbnErns)NbO,and(Sm1/6Eu1/6Y 1/6Yb1/6Lu1/6Er1/6)3(Nb1/2Ta1/2)O7 are designed and synthesized in this study.These high entropy ceramics exhibit high Vickers hardness(10.912.0 GPa),close thermal expansion coefficients to that of single-principal-component RE3TaO,and RE;NbO,(7.9×10^-6-10.8×10-6 C-1 at room temperature),good phase stability,and good chemical compatibility with thermally grown Al2O3,which make them promising for applications as candidate TBC materials. 展开更多
关键词 high entropy ceramics defective fluorite structure rare-earth niobates/tantalates thermal barrier coating material
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The first data release(DR1) of the LAMOST regular survey 被引量:29
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作者 A-Li Luo Yong-heng Zhao +134 位作者 Gang Zhao Li-Cai Deng Xiao-Wei Liu Yi-Peng Jing Gang Wang Hao-Tong Zhang Jian-Rong Shi xiang-Qun Cui Yao-Quan Chu Guo-Ping Li Zhong-Rui Bai Yue Wu Yan Cai Shu-Yun Cao Zi-Huang Cao Jeffrey L.Carlin Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Li Chen Xue-Lei Chen Xiao-Yan Chen Ying Chen Norbert Christlieb Jia-Ru Chu Chen-Zhou Cui Yi-Qiao Dong Bing Du Dong-Wei Fan Lei Feng Jian-Ning Fu Peng Gao Xue-Fei Gong Bo-Zhong Gu Yan-Xin Guo Zhan-Wen Han Bo-Liang He Jin-Liang Hou Yong-Hui Hou Wen Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Zhi-Ying Huo Lei Jia Fang-Hua Jiang xiang Jiang Zhi-Bo Jiang Ge Jin Xiao Kong Xu Kong Ya-Juan Lei Ai-Hua Li Chang-Hua Li Guang-Wei Li Hai-Ning Li Jian Li Qi Li Shuang Li Sha-Sha Li Xin-Nan Li Yan Li Yin-Bi Li Ye-Ping Li Yuan Liang Chien-Cheng Lin Chao Liu Gen-Rong Liu Guan-Qun Liu Zhi-Gang Liu Wen-Zhi Lu Yu Luo Yin-Dun Mao Heidi Newberg Ji-Jun Ni Zhao-xiang Qi Yong-Jun Qi Shi-Yin Shen Huo-Ming Shi Jing Song Yi-Han Song Ding-Qiang Su Hong-Jun Su Zheng-Hong Tang Qing-Sheng Tao Yuan Tian Dan Wang Da-Qi Wang Feng-Fei Wang Guo-Min Wang Hai Wang Hong-Chi Wang Jian Wang Jia-Ning Wang Jian-Ling Wang Jian-Ping Wang Jun-Xian Wang Lei Wang Meng-Xin Wang Shou-Guan Wang Shu-Qing Wang Xia Wang Ya-Nan Wang You Wang Yue-Fei Wang You-Fen Wang Peng Wei Ming-Zhi Wei Hong Wu Ke-Fei Wu Xue-Bing Wu Yu-Zhong Wu Xiao-Zheng Xing Ling-Zhe Xu Xin-Qi Xu Yan Xu Tai-Sheng Yan De-Hua Yang Hai-Feng Yang Hui-Qin Yang Ming Yang Zheng-Qiu Yao Yong Yu Hui Yuan Hai-Bo Yuan Hai-Long Yuan Wei-Min Yuan Chao Zhai En-Peng Zhang Hua-Wei Zhang Jian-Nan Zhang Li-Pin Zhang Wei Zhang Yong Zhang Yan-Xia Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第8期1095-1124,共30页
The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of ... The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The regular survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2 955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio(SNR) ≥ 10. All data with SNR ≥ 2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2 204 696 spectra, of which 1 944 329 are stellar spectra, 12 082 are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters: late A,FGK-type stars with high quality spectra(1 061 918 entries), A-type stars(100 073 entries), and M-type stars(121 522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided. 展开更多
关键词 techniques: spectroscopic survey—data release—catalog
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High porosity and low thermal conductivity high entropy(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2C 被引量:22
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作者 heng Chen Huimin xiang +4 位作者 Fu-Zhi Dai Jiachen Liu Yiming Lei Jie Zhang Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第8期1700-1705,共6页
Porous ultra-high temperature ceramics(UHTCs)are promising for ultrahigh-temperature thermal insulation applications.However,the main limitations for their applications are the high thermal conductivity and densificat... Porous ultra-high temperature ceramics(UHTCs)are promising for ultrahigh-temperature thermal insulation applications.However,the main limitations for their applications are the high thermal conductivity and densification of porous structure at high temperatures.In order to overcome these obstacles,herein,porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C was prepared by a simple method combing in-situ reaction and partial sintering.Porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C possesses homogeneous microstructure with grain size in the range of 100–500 nm and pore size in the range of 0.2–1μm,which exhibits high porosity of 80.99%,high compressive strength of 3.45 MPa,low room temperature thermal conductivity of 0.39 W·m^-1K^-1,low thermal diffusivity of 0.74 mm^2·s^-1and good high temperature stability.The combination of these properties renders porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))Cpromising as light-weight ultrahigh temperature thermal insulation materials. 展开更多
关键词 Ultrahigh temperature CERAMICS (UHTCs) HIGH ENTROPY CERAMICS (Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C Thermal CONDUCTIVITY POROSITY
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Transplanted human umbilical cord blood mononuclear cells improve left ventricular function through angiogenesis in myocardial infarction 被引量:20
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作者 HU Cheng-heng WU Gui-fu +4 位作者 WANG Xiao-qing YANG Yan-hua DU Zhi-min HE Xiao-hong xiang Peng 《Chinese Medical Journal》 SCIE CAS CSCD 2006年第18期1499-1506,共8页
Background Human umbilical cord blood contains an abundance of immature stem/progenitor cells, which may participate in the repair of hearts that have been damaged by myocardial infarction (MI). This study aimed to ... Background Human umbilical cord blood contains an abundance of immature stem/progenitor cells, which may participate in the repair of hearts that have been damaged by myocardial infarction (MI). This study aimed to evaluate the effects of human umbilical cord blood mononuclear cells (hUCBC) transplantation on cardiac function and left ventricular remodeling in rat model of MI. Methods Forty-five male Wistar rats were randomized into three groups: MI or control group (n=15), MI plus cell transplantation (n=15), and sham group (n=15). Acute myocardial infarction (AMI) was established by ligating the left anterior descending artery, thereafter, hUCBC were implanted into the marginal area of infarcted myocardium. In MI/control group, DMEM was injected instead of hUCBC following the same protocol. Left ventricular function assessment was carded out by echocardiography and invasive hemodynamic measurements one month post MI. All rats were sacrificed for histological and immunochemical examinations.Results The transplanted hUCBC survived and engaged in the process of myocardial repair in the host heart. Echocardiography demonstrated that left ventricular function improved significantly in the rats that underwent cell transplantation. Hemodynamic studies found a significantly decreased left ventricular end-diastolic pressure (LVEDP) [(21.08±8.10) mmHg vs (30.82±9.59) mmHg, P〈0.05], increase in +dp/dtmax [(4.29± 1.27) mmHg/ms vs (3.24±0.75) mmHg/ms, P〈0.05), and increase in -dp/dtmax [(3.71 ±0.79) mmHg/ms vs (3.00± 0.49) mmHg/ms, P〈0.05] among MI group with hUCBC transplantation when compared with MI/control group. Masson's trichrome staining revealed that the collagen density in the left ventricle was significantly lower in rats of transplantation group than that in the MI control groups [(6.33±2.69)% vs (11.10±3.75)%, P〈 0.01]. Based on immunostaining of α-actin, the numbers of microvessels were significantly (P〈0.01) increased at 展开更多
关键词 myocardial infarction cell transplantation human umbilical cord blood cells cardiac function ANGIOGENESIS
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High entropy(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12:A novel high temperature stable thermal barrier material 被引量:20
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作者 heng Chen Zifan Zhao +5 位作者 Huimin xiang Fu-Zhi Dai Wei Xu Kuang Sun Jiachen Liu Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第13期57-62,共6页
Ytterbium aluminum garnet(Yb3Al5O12)is considered as a promising thermal barrier material.However,the main limitations of Yb3Al5O12 for thermal barrier applications are relative low thermal expansion coefficient and h... Ytterbium aluminum garnet(Yb3Al5O12)is considered as a promising thermal barrier material.However,the main limitations of Yb3Al5O12 for thermal barrier applications are relative low thermal expansion coefficient and high thermal conductivity.In order to overcome these obstacles,herein,a new high entropy(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 ceramic was designed,and then powders and bulk were prepared through solid-state reaction method and spark plasma sintering(SPS),respectively.The thermal expansion coefficient of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 is(8.54±0.29)×10^-6 K^-1 at 673 K–1273 K,which is about 9%higher than that of Yb3Al5O12.The thermal conductivity of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 ceramic is 3.81 W·m^-1 K^-1 at 300 K,which is about 18%lower than that of Yb3Al5O12.Moreover,there is no reaction between HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 and thermally grown(TG)Al2O3 even at 1600℃.After annealing at 1590℃for 18 h,the average grain size of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 increases only from 1.56μm to 2.27μm.Close thermal expansion coefficient to TG Al2O3,low thermal conductivity,good phase stability,excellent chemical compatibility with TG Al2O3 and slow grain growth rate make HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 promising for thermal barrier applications. 展开更多
关键词 High entropy ceramics (Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 Thermal barrier coatings Thermal conductivity GARNET
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(Y0.25Yb0.25Er0.25Lu0.25)2(Zr0.5Hf0.5)2O7: A defective fluorite structured high entropy ceramic with low thermal conductivity and close thermal expansion coefficient to Al2O3 被引量:19
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作者 Zifan Zhao heng Chen +6 位作者 Huimin xiang Fu-Zhi Dai Xiaohui Wang Wei Xu Kuang Sun Zhijian Peng Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第4期167-172,共6页
Al2O3f/Al2O3 ceramic matrix composites(CMC)are promising candidate materials of blades and combustor liners of future gas turbines in light of their higher temperature capability,higher environmental stability and oxi... Al2O3f/Al2O3 ceramic matrix composites(CMC)are promising candidate materials of blades and combustor liners of future gas turbines in light of their higher temperature capability,higher environmental stability and oxidizing-free capacity[1–3].Nevertheless,grain growth,sintering and creep deformation at high operation temperatures are still serious problems for Al2O3f/Al2O3 ceramic matrix composites,which can lead to a reduction in the strength and damage tolerance[2].Moreover,Al2O3 can be corroded by the high temperature water vapor in combustion environments and yields volatile products,such as Al(OH)3[4].Consequently,environmental barrier coatings(EBCs)are necessary for Al2O3f/Al2O3 ceramic matrix composites,which can protect Al2O3f/Al2O3 CMC from high temperature and flowing combustion gas corrosion and thus increase the high temperature capability and the service life of components. 展开更多
关键词 Al2O3f/Al2O3 CERAMIC matrix CONDUCTIVITY CLOSE thermal expansion
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Porous high entropy(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2: A novel strategy towards making ultrahigh temperature ceramics thermal insulating 被引量:18
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作者 heng Chen Huimin xiang +2 位作者 Fu-Zhi Dai Jiachen Liu Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第10期2404-2408,共5页
Transition metal diborides based ultrahigh temperature ceramics(UHTCs) are characterized by high melting point, high strength and hardness, and high electrical and thermal conductivity. The high thermal conductivity a... Transition metal diborides based ultrahigh temperature ceramics(UHTCs) are characterized by high melting point, high strength and hardness, and high electrical and thermal conductivity. The high thermal conductivity arises from both electronic and phonon contributions. Thus electronic and phonon contributions must be controlled simultaneously in reducing the thermal conductivity of transition metal diborides. In high entropy(HE) materials, both electrons and phonons are scattered such that the thermal conductivity can significantly be reduced, which opens a new window to design novel insulating materials. Inspired by the high entropy effect, porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 is designed in this work as a new thermal insulting ultrahigh temperature material and is synthesized by an in-situ thermal borocarbon reduction/partial sintering process. The porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 possesses high porosity of 75.67%, pore size of 0.3–1.2 μm, homogeneous microstructure with small grain size of 400–800 nm, which results in low room temperature thermal diffusivity and thermal conductivity of 0.74 mm2 s^-1 and 0.51 W m^-1K^-1, respectively. In addition, it exhibits high compressive strength of3.93 MPa. The combination of these properties indicates that exploring porous high entropy ceramics such as porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 is a novel strategy in making UHTCs thermal insulating. 展开更多
关键词 High entropy ceramics (Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 Transition metal diborides Porous materials Thermal insulating In-situ reaction/partial sintering
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High entropy(Yb0.25Y0.25Lu0.25Er0.25)2SiO5 with strong anisotropy in thermal expansion 被引量:18
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作者 heng Chen Huimin xiang +2 位作者 Fu-Zhi Dai Jiachen Liu Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第1期134-139,共6页
A novel high entropy(HE) rare earth monosilicate(Yb0.25Y0.25Lu0.25Er0.252 SiO5 was synthesized by solid-state reaction method.X-ray diffraction and scanning electron microscopy analysis indicate that a single solid so... A novel high entropy(HE) rare earth monosilicate(Yb0.25Y0.25Lu0.25Er0.252 SiO5 was synthesized by solid-state reaction method.X-ray diffraction and scanning electron microscopy analysis indicate that a single solid solution is formed with homogeneous distribution of rare-earth elements.HE(Yb0.25Y0.25Lu0.255 Er0.252 SiO5 exhibits excellent phase stability and anisotropy in thermal expansion.The coefficients of thermal expansion(CTEs) in three crystallographic directions are:αa=(2.57±0.07)×10^-6 K^-1,αb=(8.07±0.13)×10^-6 K^-1,αc=(9.98±0.10)×10^-6 K^-1.The strong anisotropy in thermal expansion is favorable in minimizing the coating/substrate mismatch if preferred orientation of HE(Yb0.25Y0.25Lu0.25Er0.252 SiO5 is controlled on either metal or ceramic substrate. 展开更多
关键词 HIGH ENTROPY ceramics RARE earth monosilicates SOLID-STATE reaction Thermal expansion ANISOTROPY
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(La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4: A high-entropy rare-earth phosphate monazite ceramic with low thermal conductivity and good compatibility with Al2O3 被引量:18
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作者 Zifan Zhao heng Chen +4 位作者 Huimin xiang Fu-Zhi Dai Xiaohui Wang Zhijian Peng Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第12期2892-2896,共5页
Low thermal conductivity, matched thermal expansion coefficient and good compatibility are general requirements for the environmental/thermal barrier coatings(EBCs/TBCs) and interphases for Al2O3 f/Al2O3 composites. I... Low thermal conductivity, matched thermal expansion coefficient and good compatibility are general requirements for the environmental/thermal barrier coatings(EBCs/TBCs) and interphases for Al2O3 f/Al2O3 composites. In this work, a novel high-entropy(HE) rare-earth phosphate monazite ceramic (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 is designed and successfully synthesized. This new type of HE rare-earth phosphate monazite exhibits good chemical compatibility with Al2O3, without reaction with Al2O3 as high as 1600℃ in air. Moreover, the thermal expansion coefficient(TEC) of HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4(8.9 × 10^-6/℃ at 300–1000℃) is close to that of Al2O3. The thermal conductivity of HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 at room temperature is as low as 2.08 W·m^-1·K^-1, which is about 42% lower than that of La PO4. Good chemical compatibility, close TEC to that of Al2O3, and low thermal conductivity indicate that HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 is suitable as a candidate EBC/TBC material and an interphase for Al2O3 f/Al2O3 composites. 展开更多
关键词 (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 High-entropy ceramics Al2O3f/Al2O3ceramic matrix composites Environmental barrier coating materials Interphase material Thermal expansion coefficient Thermal conductivity Solution synthesis Rare-earth phosphates MONAZITE
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Effects of Limiting Amino Acids on Rumen Fermentation and Microbial Community In vitro 被引量:17
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作者 WANG Meng-zhi WANG Hong-rong CAO heng-chun LI Guo-xiang ZHANG Jie 《Agricultural Sciences in China》 CAS CSCD 2008年第12期1524-1531,共8页
Three goats fitted with cannula were used to provide rumen liquor to investigate the effects of limiting amino acids on rumen fermentation and microbial community in vitro. The removal method was used in the current e... Three goats fitted with cannula were used to provide rumen liquor to investigate the effects of limiting amino acids on rumen fermentation and microbial community in vitro. The removal method was used in the current experiments. Treatments are total essential amino acid (TEAA), His-removal, Lys-removal, Met-removal, and branch chain amino acid (BCAA)- removal. Results indicated that, pH-value ranged between 5.9 and 6.8, with the highest mean value for the group with BCAA-removal (6.54) in the culture. Concentration of NH3-N ranged between 10.99 to 30.51 mg 100 mL^-1, with the group of TEAA recording the highest average NH3-N concentration (17.85 mg 100 mL^-1). Yields of microbial protein and limiting degree on microbial growth varied with treatments (P 〈 0.01), and the lowest accrued in treatment with BCAA-removal (0.1389, 0.1772, and 0.3161 mg mL^-1 for bacteria, protozoa, and mixed microbes, respectively), compared to the group with TEAA, microbial production of mixed microbes decreased by 44.52%. As for micro-flora, protozoa to bacteria ratio was the lowest for the group with Lys-removal (89.12%), while the highest for the group with BCAA-removal (127.60%) (P 〈 0.01). Furthermore, PCR-SSCP analysis revealed that, microbial profile subjected to substrates within bacteria and protozoa groups. It was therefore concluded that, dietary amino acid influenced both rumen fermentation and microbial characteristics. 展开更多
关键词 limiting amino acids rumen microbes limiting degree
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Electromagnetic wave absorbing properties of TMCs(TM=Ti,Zr,Hf,Nb and Ta)and high entropy(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C 被引量:16
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作者 Yanchun Zhou Biao Zhao +4 位作者 heng Chen Huimin xiang Fu-Zi Dai Shijiang Wu Wei Xu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第15期105-118,共14页
Electromagnetic wave(EMW)absorbing materials play a vital role in modern communication and information processing technologies to inhibit information leakage and prevent possible damages to environment and human bodie... Electromagnetic wave(EMW)absorbing materials play a vital role in modern communication and information processing technologies to inhibit information leakage and prevent possible damages to environment and human bodies.Currently,most of EMW absorbing materials are either composites of two or more phases or in the form of nanosheets,nanowires or nanofibers in order to enhance the EMW absorption performance through dielectric loss,magnetic loss and dielectric/magnetic loss coupling.However,the combination of complex shapes/multi phases and nanosizes may compound the difficulties of materials processing,composition and interfaces control as well as performance maintenance during service.Thus,searching for single phase materials with good stability and superior EMW absorbing properties is appealing.To achieve this goal,the EMW absorbing properties of transition metal carbides TMCs(TM=Ti,Zr,Hf,Nb and Ta)and high entropy(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C which belong to ultrahigh temperature ceramics,were investigated in this work.Due to the good electrical conductivity and splitting of d orbitals into lower energy t2glevel and higher energy eglevel in TMC6octahedral arrangement,TMCs(TM=Ti,Zr,Hf,Nb and Ta)exhibit good EMW absorbing properties.Especially,Hf C and Ta C exhibit superior EMW absorbing properties.The minimum reflection loss(RLmin)value of Hf C is-55.8 d B at 6.0 GHz with the thickness of 3.8 mm and the effective absorption bandwidth(E_(AB))is 6.0 GHz from 12.0 to 18.0 GHz at thickness of 1.9 mm;the RL_(minvalue)of Ta C reaches-41.1 d B at 16.2 GHz with a thickness of 2.0 mm and the EABis 6.1 GHz with a thickness of 2.2 mm.Intriguingly,the electromagnetic parameters,i.e.,complex permittivity and permeability are tunable by forming single phase solid solution or high entropy(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C.The R_(Lminvalue)of high entropy(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C is-38.5 d B at 9.5 GHz with the thickness of 1.9 mm,and the EABis 2.3 GHz(from 11.3 to 13.6 GHz)at thickness o 展开更多
关键词 Transition metal carbides High entropy ceramics Microwave absorption Electromagnetic parameters Electronic structure Crystal field theory
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中国泡菜发酵态相对稳定性的研究及应用 被引量:15
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作者 陈功 张其圣 +7 位作者 李恒 唐垚 汪冬冬 伍亚龙 朱翔 张伟 余文华 游敬刚 《食品与发酵科技》 CAS 2020年第1期54-63,72,共11页
中国泡菜以四川泡菜为代表,发酵是其基本的状态(简称发酵态),而主导微生物是泡菜发酵的源动力。在系统研究的基础上,论文阐述了泡菜发酵原理、菌群结构的演变、主导微生物及其数量变化、发酵态的变化及其稳定系统(稳态)的形成、稳态的... 中国泡菜以四川泡菜为代表,发酵是其基本的状态(简称发酵态),而主导微生物是泡菜发酵的源动力。在系统研究的基础上,论文阐述了泡菜发酵原理、菌群结构的演变、主导微生物及其数量变化、发酵态的变化及其稳定系统(稳态)的形成、稳态的应用。揭示了我国传统泡菜发酵是动态和稳态的两个关键状态的演变过程,其中动态又包含启动态和非稳态。基于泡菜稳态的形成及其特征指标,首次正式提出“稳态发酵理论”。在该理论的指导下,实现了泡菜现代化发酵加工生产,并保持了传统泡菜风味,既传承了经典泡菜工艺,又创新引领了泡菜产业的发展。 展开更多
关键词 泡菜 微生物演变 稳态发酵 传承创新 应用
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中国光线性角化病临床诊疗专家共识(2021) 被引量:15
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作者 中国康复医学会皮肤病康复专业委员会 中华医学会皮肤性病学分会光动力治疗研究中心 +3 位作者 中国医学装备协会皮肤病与皮肤美容分会光医学治疗装备学组 王秀丽 顾恒 陈翔 《中华皮肤科杂志》 CAS CSCD 北大核心 2021年第12期1048-1056,共9页
光线性角化病是一种慢性进行性癌前病变,可进展为皮肤鳞状细胞癌。随着中国患病人数逐渐增多,亟须建立合适的诊断及治疗规范。中国康复医学会皮肤病康复专业委员会、中华医学会皮肤性病学分会联合中国医学装备协会皮肤病与皮肤美容分会... 光线性角化病是一种慢性进行性癌前病变,可进展为皮肤鳞状细胞癌。随着中国患病人数逐渐增多,亟须建立合适的诊断及治疗规范。中国康复医学会皮肤病康复专业委员会、中华医学会皮肤性病学分会联合中国医学装备协会皮肤病与皮肤美容分会组织光线性角化病相关领域部分专家,在国内外文献数据、国际指南和专家临床经验的基础上,结合我国诊疗现状,制定中国光线性角化病临床诊疗专家共识。本共识从光线性角化病的流行病学、发病因素及临床转归、临床表现及分级、诊断及鉴别诊断、治疗策略和患者教育管理等方面进行阐述,诊断方面包含了皮肤镜、反射式共聚焦显微镜和皮肤病理等手段,治疗策略涵盖了常见局部治疗和系统治疗方法,局部治疗包括光动力治疗、外用药物、物理治疗和手术切除,且按照证据等级给予推荐级别,为皮肤科医师诊疗工作提供参考。 展开更多
关键词 角化病 光化性 诊断 治疗学 专家共识
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Achieving strong microwave absorption capability and wide absorption bandwidth through a combination of high entropy rare earth silicide carbides/rare earth oxides 被引量:14
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作者 heng Chen Biao Zhao +4 位作者 Zifan Zhao Huimin xiang Fu-Zhi Dai Jiachen Liu Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第12期216-222,共7页
Developing electromagnetic(EM) wave absorbing materials with low reflection coefficient and optimal operating frequency band is urgently needed on account of the increasingly serious EM pollution. However, the applica... Developing electromagnetic(EM) wave absorbing materials with low reflection coefficient and optimal operating frequency band is urgently needed on account of the increasingly serious EM pollution. However, the applications of common EM absorbing materials are encumbered by poor high-temperature stability, poor oxidation resistance, narrow absorption bandwidth or high density. Herein, the strong EM absorption capability and wide efficient absorption bandwidth of high entropy ceramics are reported for the first time, which are designed by a combination of the novel high entropy(HE) rare earth silicide carbides/rare earth oxides(RE3 Si2 C2/RE2 O3). Three HE powders, i.e., HERSC-1(HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2),HERSC-2 HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2/HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)2 O3) and HERSC-3(HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2/HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)2 O3), are synthesized. Although HERSC-1 exhibits a limited absorption effect(the minimum reflection loss(RLmin) is-11.6 d B at 3.4 mm) and a relatively narrow effective absorption bandwidth(EAB) of 1.7 GHz, the optimal absorption RLminvalue and EAB of HERSC-2 and HERSC-3 are-40.7 d B(at 2.9 mm), 3.4 GHz and-50.9 d B(at 2.0 mm), 4.5 GHz,respectively, demonstrating strong microwave absorption capability and wide absorption bandwidth.Considering the better stability, low density and strong EM absorption effect, HE ceramics are promising as a new type of EM absorbing materials. 展开更多
关键词 High entropy ceramics Rare earth silicide carbides Absorption materials Reflection loss Interfacial polarization
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Clinical practice guideline for transurethral plasmakinetic resection of prostate for benign prostatic hyperplasia(2021 Edition) 被引量:12
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作者 Xian-Tao Zeng Ying-Hui Jin +45 位作者 Tong-Zu Liu Fang-Ming Chen De-Gang Ding Meng Fu Xin-Quan Gu Bang-Min Han Xing Huang Zhi Hou Wan-Li Hu Xin-Li Kang Gong-Hui Li Jian-Xing Li Pei-Jun Li Chao-Zhao Liang Xiu-heng Liu Zhi-Yu Liu Chun-Xiao Liu Jiu-Min Liu Guang-heng Luo Yi Luo Wei-Jun Qin Jian-Hong Qiu Jian-Xin Qiu Xue-Jun Shang Ben-Kang Shi Fa Sun Guo-xiang Tian Ye Tian Feng Wang Feng Wang Yin-Huai Wang Yu-Jie Wang Zhi-Ping Wang Zhong Wang Qiang Wei Min-Hui Xiao Wan-Hai Xu Fa-Xian Yi Chao-Yang Zhu Qian-Yuan Zhuang Li-Qun Zhou Xiao-Feng Zou Nian-Zeng Xing Da-Lin He Xing-Huan Wang 《Military Medical Research》 SCIE CAS CSCD 2022年第5期515-533,共19页
Benign prostatic hyperplasia (BPH) is highly prevalent among older men, impacting on their quality of life, sexual function, and genitourinary health, and has become an important global burden of disease. Transurethra... Benign prostatic hyperplasia (BPH) is highly prevalent among older men, impacting on their quality of life, sexual function, and genitourinary health, and has become an important global burden of disease. Transurethral plasmakinetic resection of prostate (TUPKP) is one of the foremost surgical procedures for the treatment of BPH. It has become well established in clinical practice with good efficacy and safety. In 2018, we issued the guideline “2018 Standard Edition”. However much new direct evidence has now emerged and this may change some of previous recommendations. The time is ripe to develop new evidence-based guidelines, so we formed a working group of clinical experts and methodologists. The steering group members posed 31 questions relevant to the management of TUPKP for BPH covering the following areas: questions relevant to the perioperative period (preoperative, intraoperative, and postoperative) of TUPKP in the treatment of BPH, postoperative complications and the level of surgeons’ surgical skill. We searched the literature for direct evidence on the management of TUPKP for BPH, and assessed its certainty generated recommendations using the grade criteria by the European Association of Urology. Recommendations were either strong or weak, or in the form of an ungraded consensus-based statement. Finally, we issued 36 statements. Among them, 23 carried strong recommendations, and 13 carried weak recommendations for the stated procedure. They covered questions relevant to the aforementioned three areas. The preoperative period for TUPKP in the treatment of BPH included indications and contraindications for TUPKP, precautions for preoperative preparation in patients with renal impairment and urinary tract infection due to urinary retention, and preoperative prophylactic use of antibiotics. Questions relevant to the intraoperative period incorporated surgical operation techniques and prevention and management of bladder explosion. The application to different populations incorporating the efficacy an 展开更多
关键词 Transurethral plasmakinetic resection of prostate Benign prostatic hyperplasia RECOMMENDATION TREATMENT GUIDELINE
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云环境中的多授权机构访问控制方案 被引量:13
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作者 郑良汉 何亨 +2 位作者 童潜 杨湘 陈享 《计算机科学与探索》 CSCD 北大核心 2020年第11期1865-1878,共14页
密文策略属性加密(CP-ABE)十分适用于云环境中的数据访问控制。现有的CP-ABE算法未考虑多个文件的访问结构具有层次关系,需要对每个文件分别加密实现其访问控制需求,导致较大的开销;此外,大多数方案只有单个授权机构管理密钥,对授权机... 密文策略属性加密(CP-ABE)十分适用于云环境中的数据访问控制。现有的CP-ABE算法未考虑多个文件的访问结构具有层次关系,需要对每个文件分别加密实现其访问控制需求,导致较大的开销;此外,大多数方案只有单个授权机构管理密钥,对授权机构的安全性与可靠性要求极高。提出一种云环境中基于区块链的多授权机构访问控制方案(BMAC)。在BMAC中,设计了一种层次化CP-ABE算法,对于具有层次关系的多个文件,仅需加密一次,访问者在满足部分访问条件时能解密得到部分文件,满足全部条件时得到全部文件;设计了一种基于区块链的多授权机构密钥管理方法,通过区块链技术使得所有授权机构能够诚实并行地进行私钥分发。安全性与性能分析验证了BMAC能够有效保障数据机密性,抵抗串谋攻击,实现安全高效的细粒度数据访问控制以及去中心化的私钥分发。 展开更多
关键词 云计算 访问控制 属性加密 多授权机构 区块链
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