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Scientific Advances and Weather Services of the China Meteorological Administration’s National Forecasting Systems during the Beijing 2022 Winter Olympics
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作者 Guo DENG Xueshun SHEN +23 位作者 Jun DU Jiandong GONG Hua TONG Liantang DENG Zhifang XU Jing CHEN Jian SUN Yong WANG Jiangkai HU Jianjie WANG Mingxuan CHEN Huiling YUAN Yutao ZHANG Hongqi LI Yuanzhe WANG Li GAO Li SHENG Da LI Li LI Hao WANG Ying ZHAO Yinglin LI Zhili LIU Wenhua GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期767-776,共10页
Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational... Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational techniques,and experience.This made providing meteorological services for this event particularly challenging.The China Meteorological Administration(CMA)Earth System Modeling and Prediction Centre,achieved breakthroughs in research on short-and medium-term deterministic and ensemble numerical predictions.Several key technologies crucial for precise winter weather services during the Winter Olympics were developed.A comprehensive framework,known as the Operational System for High-Precision Weather Forecasting for the Winter Olympics,was established.Some of these advancements represent the highest level of capabilities currently available in China.The meteorological service provided to the Beijing 2022 Games also exceeded previous Winter Olympic Games in both variety and quality.This included achievements such as the“100-meter level,minute level”downscaled spatiotemporal resolution and forecasts spanning 1 to 15 days.Around 30 new technologies and over 60 kinds of products that align with the requirements of the Winter Olympics Organizing Committee were developed,and many of these techniques have since been integrated into the CMA’s operational national forecasting systems.These accomplishments were facilitated by a dedicated weather forecasting and research initiative,in conjunction with the preexisting real-time operational forecasting systems of the CMA.This program represents one of the five subprograms of the WMO’s high-impact weather forecasting demonstration project(SMART2022),and continues to play an important role in their Regional Association(RA)II Research Development Project(Hangzhou RDP).Therefore,the research accomplishments and meteorological service experiences from this program will be carried forward into forthcoming highimpact weather forecasting activities.This article provides an overview and assessment of this program and the operational national forecasting systems. 展开更多
关键词 Beijing Winter olympic Games CMA national forecasting system data assimilation ensemble forecast bias correction and downscaling machine learning-based fusion methods
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National Image Construction from the Perspective of Multimodal Metaphor-A Case Study of the Opening Ceremony of the Beijing Winter Olympics
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作者 LUO Yi ZHOU Jing 《Journal of Literature and Art Studies》 2024年第4期290-294,共5页
The national image is a comprehensive concept with a distinct political feature,including the international image presented to the outside world,and also encompassing the national identity of the people.With the devel... The national image is a comprehensive concept with a distinct political feature,including the international image presented to the outside world,and also encompassing the national identity of the people.With the development of globalization,international cultural communication has become a crucial part of shaping the national image,and the opening ceremony of the Beijing Winter Olympics has become an important opportunity for China to showcase its national image to the world in the post-pandemic era.Based on Forceville’s multimodal metaphor theory,this paper examines the metaphorical phenomena contained in the performance and their functions,effects,and purposes in the construction of the national image.It is found that there are many scenes,images,and narratives in the opening ceremony,including war metaphor,competition metaphor,personification metaphor,and other conceptual metaphors.The focus of this paper is on multimodal metaphor in a broad sense,mainly encompassing auditory and visual modes.Through the use of these multimodal metaphors,the opening ceremony of the Winter Olympics builds an image of a vibrant,peace-loving,and responsible country,which not only demonstrates China’s cultural self-confidence,but also expresses the Chinese people’s beautiful vision for the early reunification of the motherland. 展开更多
关键词 multimodal metaphor national image olympic Winter Games Opening Ceremony
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Accessibility of Urban Rail Transit in Post-Winter Olympics Period Based on Internet Map: A Case Study of Beijing
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作者 LI Daoyong ZANG Hengyi HE Qilin 《Journal of Landscape Research》 2022年第5期16-18,共3页
After the Winter Olympics,Beijing proposed to speed up the construction of rail transit.Taking Beijing as the research object,the accessibility of rail transit stations in the 6 districts of the city were analyzed by ... After the Winter Olympics,Beijing proposed to speed up the construction of rail transit.Taking Beijing as the research object,the accessibility of rail transit stations in the 6 districts of the city were analyzed by using POI services and route planning services provided by Internet map providers,relying on ArcMap10.6 platform.The research holds that the development of rail transit in Beijing is not sufficient and unbalanced.Network density has an important influence on the accessibility of rail transit stations.The travel mode of rail transit + cycling can improve the accessibility of stations in underdeveloped areas.In Shijingshan District,the accessibility of rail transit stations in the region can be improved by optimizing the slow traveling environment between the Winter Olympics branch line,Subway Line 6 and Subway Line 1. 展开更多
关键词 Post-Winter olympics TOD Rail transit Internet map ACCESSIBILITY
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Preliminary Discussion on the Sea Water Quality Status in the 2008 Olympics Boat-sailing Field and Adjacent Area 被引量:1
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作者 石晓勇 陈莉莉 +1 位作者 祝陈坚 王修林 《Marine Science Bulletin》 CAS 2007年第2期90-96,共7页
A cruise of survey in the 2008 Olympics boat-sailing field and adjacent area was carried out on August 28^th, 2003. Preliminarily analysis on the eutrophication status was made on the basis of the content of dissolved... A cruise of survey in the 2008 Olympics boat-sailing field and adjacent area was carried out on August 28^th, 2003. Preliminarily analysis on the eutrophication status was made on the basis of the content of dissolved inorganic nitrogen (DIN), dissolved inorganic phosphate (PO4-P), dissolved oxygen(DO) and chemical oxygen demand (COD) as well. The results indicated that in most of the survey area, water quality was in accordance with the 1^st class National Seawater Standard except the average concentration of petroleum hydrocarbon which was beyond the 2^nd class National Seawater Standard. The concentrations of PO4-P as well as DIN were mainly influenced by the runoff or drainage from lands, with a comparatively higher concentration in the coastal areas from the Fushan Bay to the Shilaoren bathing beach. The distribution of eutrophication index (El) showed that part of the survey area was in a state of slight eutrophication The eutrophication was mostly influenced by the land runoff or drainage and related factors. The sea water quality of the Olympic boat-sailing field was fine and just slightly polluted on the whole. 展开更多
关键词 the 2008 olympic boat-sailing field nutrients EUTROPHICATION pollution
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The Structure and Evolution of Sea Breezes During the Qingdao Olympics Sailing Test Event in 2006 被引量:6
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作者 盛春岩 Ming XUE 高守亭 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第1期132-142,共11页
Using data from automatic surface weather stations, buoys, lidar and Doppler, the diurnal variation and the three-dimensional structure of the sea breezes near the sailing sites of the Good Luck Beijing- 2006 Qingdao ... Using data from automatic surface weather stations, buoys, lidar and Doppler, the diurnal variation and the three-dimensional structure of the sea breezes near the sailing sites of the Good Luck Beijing- 2006 Qingdao International Regatta from 18 to 31 August 2006 are analyzed. Results show that excluding rainy days and days affected by typhoon, the sea breezes occur nearly every day during this period. When Qingdao is located at the edge of the subtropical high at 500 hPa, the sea breeze is usually stronger, around 3-4 m s^-1. It starts at around 1100 to 1300 LST and lasts about 6 hours. The direction of the sea breeze tends to be southeasterly. When Qingdao is under the control of the subtropical high, the sea breeze is usually weaker, less than 2.5 m s^-1 throughout the day, and begins later, between 1300 and 1500 LST. In this case, the direction of the sea breeze is variable from easterly to southeasterly. Most sea breezes in Qingdao are very shallow, up to 300 meters deep. Strong sea breezes can reach 1.5 km in depth and can push as far as 100 km inland. If the Huanghai sea breeze moves inland and meets the sea breeze of the Jiaozhou Bay in the western part of Qingdao, the sea breeze will strengthen and form three boundaries due to the interaction of the two sea breezes. 展开更多
关键词 olympic sailing sea breeze local coastal winds
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SARS-Cov-2 Delayed Tokyo 2020 Olympics: Very Recent Advances in COVID-19 Detection, Treatment, and Vaccine Development Useful Conducting the Games in 2021 被引量:3
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作者 Zameer Shervani Intazam Khan Umair Yaqub Qazi 《Advances in Infectious Diseases》 2020年第3期56-66,共11页
The novel coronavirus (SARS-Cov-2) delayed the Tokyo 2020 Games. The traveling by air, rail, road, and sea inside and outside the countries has stopped to contain the virus. The amount of money lost and assistance nee... The novel coronavirus (SARS-Cov-2) delayed the Tokyo 2020 Games. The traveling by air, rail, road, and sea inside and outside the countries has stopped to contain the virus. The amount of money lost and assistance needed to reschedule and conduct the Games in 2021 have been estimated. With more than one billion population is under the semi-locked down and movement of people is restricted, athletes cannot prepare at home and participate in the Games. The COVID-19 outbreak has spread around the world;it has already infected 5.7 million people and caused 355,000 deaths reported on May 28, 2020 and the figures increasing every day. The publication of this article is important as the postponement of the Olympics has costed Japan $6 billion and the organizers have worked very hard for seven years. If the Games are conducted in 2021, it will be the—beginning of the world recovery—from big COVID-19 pandemic. In this communication, the development in testing, treatment, and vaccine preparation for SARS-Cov-2 have occurred so far in different countries and companies have been discussed to know the possibilities if the pandemic can be overcome and the Games can be conducted in 2021. 展开更多
关键词 COVID-19 SARS-Cov-2 Tokyo 2020 olympics COVID-19 Detection SARS-Cov-2 Treatment COVID-19 Vaccine
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Transport Patterns and Potential Sources of Atmospheric Pollution during the ⅩⅩⅣ Olympic Winter Games Period 被引量:2
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作者 Yuting ZHANG Xiaole PAN +15 位作者 Yu TIAN Hang LIU Xueshun CHEN Baozhu GE Zhe WANG Xiao TANG Shandong LEI Weijie YAO Yuanzhe REN Yongli TIAN Jie LI Pingqing FU Jinyuan XIN Yele SUN Junji CAO Zifa WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第10期1608-1622,I0002-I0004,共18页
The attainment of suitable ambient air quality standards is a matter of great concern for successfully hosting the ⅩⅩⅣ Olympic Winter Games(OWG). Transport patterns and potential sources of pollutants in Zhangjiako... The attainment of suitable ambient air quality standards is a matter of great concern for successfully hosting the ⅩⅩⅣ Olympic Winter Games(OWG). Transport patterns and potential sources of pollutants in Zhangjiakou(ZJK) were investigated using pollutant monitoring datasets and a dispersion model. The PM_(2.5) concentration during February in ZJK has increased slightly(28%) from 2018 to 2021, mostly owing to the shift of main potential source regions of west-central Inner Mongolia and Mongolian areas(2015–18) to the North China Plain and northern Shanxi Province(NCPS) after 2018.Using CO as an indicator, the relative contributions of the different regions to the receptor site(ZJK) were evaluated based on the source-receptor-relationship method(SRR) and an emission inventory. We found that the relative contribution of pollutants from NCPS increased from 33% to 68% during 2019–21. Central Inner Mongolia(CIM) also has an important impact on ZJK under unfavorable weather conditions. This study demonstrated that the effect of pollution control measures in the NCPS and CIM should be strengthened to ensure that the air quality meets the standard during the ⅩⅩⅣ OWG. 展开更多
关键词 olympic Winter Games FLEXPART transport characteristics atmospheric pollution sources
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Assessing vegetation community distribution characteristics and succession stages in mountainous areas hosting coming Winter Olympics Games 被引量:1
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作者 ZHANG Heng-shuo ZHA Tong-gang +2 位作者 YU Yang JI Xiao-dong JESÚS Rodrigo-Comino 《Journal of Mountain Science》 SCIE CSCD 2021年第11期2870-2887,共18页
Alpine mountain ecosystem shows strong interactions between abiotic and biotic parameters.They also receive high attention from human activities(natural tourism,trekking,skiing,etc.).However,as the potential disturban... Alpine mountain ecosystem shows strong interactions between abiotic and biotic parameters.They also receive high attention from human activities(natural tourism,trekking,skiing,etc.).However,as the potential disturbance risk areas in alpine mountains are increasing,it is necessary to understand the relationship between environmental factors and plant communities.This is also the key consideration for the coming international events such as the Winter Olympic Games,which could generate uncontrolled ecosystem issues not previously studied.The Yin Mountains in Chongli district,Zhangjiakou City,Hebei Province,China will be the core area of the 2022 Winter Olympic Games.We hypothesize that disturbances will be caused,therefore,the previous relationships between the habitat factors and plant community and the main environmental limiting factors before hosting them must be assessed to design future restoration plans.Therefore,we used the two-way indicator species analysis(TWINSPAN)and market basket analysis(MBA)for vegetation classification in 91 sampling plots.Plant community and relationships among environmental variables(altitude,slope position,aspect,direction,inclination,soil porosity,soil bulk density,organic matter content and soil pH)were investigated through the trend correspondence(DCA)and canonical correspondence analyses(CCA).Also,the TWINSPAN was used to classify the vegetation into 6 different groups.CCA analysis showed that i)the spatial variation of soil moisture and the content of soil organic matter are the main factors limiting the development of shrub and herb communities;ii)the distribution of different forest communities was mainly affected by terrain factors(altitude,aspect and slope position);iii)the dynamic changes of vegetation communities in different altitudes were affected by the fluctuation of environmental factors and human disturbance,and the shrubs and herbaceous plants in mid-to-high altitude areas(above 1400 m)generally show the process of transformation from the pioneer community to transitional community in the competition.We concluded that under the strong interference of human activities in the core construction area of the Olympic venues,higher damage intensity and lower resilience in the low altitude area is observed compared with the pioneer community.Whereas in the low altitude area(below 1400m)with a fragile ecological environment,although the plant diversity and coverage are poor,the potential impact and damage degree of the Olympic Games are greatly reduced due to the distance from the construction area of the core venues and good resilience.This information can help land managers and policymakers to anticipate human disturbances on plant communities and support guiding the most efficient ecological restoration after the Winter Olympic Games in 2022. 展开更多
关键词 Vegetation classification Topographic factors Community distribution Winter olympic Games
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鼻咽癌中Period2下调ERK/MAPK磷酸化水平的机制
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作者 张志娟 马政 +7 位作者 康晶 杨敬 徐倩茹 牛欣冉 罗小丫 王婧媛 李海亮 侯丽 《广东医学》 CAS 2024年第10期1255-1265,共11页
目的探讨生物钟基因Period2在鼻咽癌中下调ERK/MAPK磷酸化水平的分子机制。方法用慢病毒对细胞进行感染,构建细胞系。采用Label-free蛋白质组学检测方法对PER2蛋白表达进行验证。采用不同浓度的ERK通路激活剂Ceramide C6干预各组细胞,MT... 目的探讨生物钟基因Period2在鼻咽癌中下调ERK/MAPK磷酸化水平的分子机制。方法用慢病毒对细胞进行感染,构建细胞系。采用Label-free蛋白质组学检测方法对PER2蛋白表达进行验证。采用不同浓度的ERK通路激活剂Ceramide C6干预各组细胞,MTT检测各组细胞的增殖能力,筛选最佳药物浓度和作用时间。采用ERK通路激活剂Ceramide C6干预细胞,正常对照组采用等剂量药物溶剂进行处理,分为6组。Western blot检测各组细胞PER2、ERK、p38MAPK、p-ERK、p-p38MAPK蛋白的表达。流式细胞术检测细胞周期,Transwell实验检测各组细胞侵袭能力,进一步明确PER2调控ERK、MAPK磷酸化的机制。用免疫组化检测PER2、p-ERK在人体鼻咽癌样本中的表达,并分析PER2、p-ERK与鼻咽癌临床特点的相关性。结果蛋白质组学检测结果示PER2过表达组的PER2蛋白表达明显高于阴性病毒对照组和空白对照组(P<0.05)。Top 20差异蛋白显示MAPK3在PER2过表达组和对照组差异有统计学意义(P<0.05)。MTT实验结果:不同药物浓度处理后,根据每组细胞抑制率,得出最佳的药物作用浓度10μmol/L,最佳处理时间24 h。WB结果显示PER2过表达下调p-ERK、p-p38MAPK蛋白表达,ERK通路激活剂Ceramide C6干预后,在PER2-OE组中ERK、p38MAPK蛋白水平无明显变化,但p-ERK、p-p38MAPK蛋白表达水平上调,干预前后差异有统计学意义(P<0.01)。细胞周期实验结果显示:ERK通路激活剂Ceramide C6干预各组细胞后,使细胞在G1期的比例明显增加,而在G2期数量减少。Transwell实验结果显示PER2过表达抑制细胞侵袭能力,此种现象不能被磷酸激酶逆转。在鼻咽癌组织、鼻咽部黏膜中PER2蛋白、p-ERK蛋白表达阳性率差异有统计学意义(P<0.05)。PER2蛋白表达与肿瘤的T分期相关(P<0.05)。在鼻咽癌组织中PER2蛋白与p-ERK蛋白表达相关(P<0.05)。结论PER2过表达下调ERK/MAPK磷酸化水平,可能不是直接作用于ERK和p38MAPK的磷酸化位点,而是与调控ERK和p38MAPK的关键节点有关。鼻咽癌组织中PER2蛋白呈低表达,p-ERK蛋白呈高表达,两者相关,并且与肿瘤的发生、发展关系密切。 展开更多
关键词 鼻咽癌 period2 生物节律 ERK/MAPK信号通路
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Artificial Seeding Effects of Convective Clouds on the Opening Day of Beijing 2008 Summer Olympics
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作者 Hongyu Li Yanping Dai +1 位作者 Hua Wang Jingang Cui 《Journal of Geoscience and Environment Protection》 2017年第4期118-138,共21页
Using the radar reflectivity and intensive rainfall data, artificial seeding effects of convective clouds in Beijing on 8 August 2008, the opening day of the 29th Summer Olympics, were analyzed. The results indicate t... Using the radar reflectivity and intensive rainfall data, artificial seeding effects of convective clouds in Beijing on 8 August 2008, the opening day of the 29th Summer Olympics, were analyzed. The results indicate that, cloud seeding at single operation site for convective clouds invading from southwest direction may sharply mitigate the rainfall observed at leeward automatic weather stations within 5 - 10 min, while enhances the precipitation at a later stage about 10 - 20 min. Cloud seeding effects of operation sites Yuegezhuangxi, Changgouzhen, and Zhoukou, which are placed along the main moving routes or localized developing convective clouds in the west and center parts of Fangshan district, are very conspicuous. Combining the operation sites distribution and radar echoes, it is found that the site Changgouzhen, which is very close to the convective core, plays an essential role in suppressing the growth of convective cloud, reducing the coverage area of intense echoes classified as 45 - 60 dBZ, as well as mitigating the precipitation from neighboring automatic weather stations. Based on radar reflectivity and rainfall data, we find that the clouds over lots of operation sites in eastern Fangshan district are not cold enough to favor glaciogenic seeding with silver iodide, meanwhile, there is not too much precipitation observed. 展开更多
关键词 Cloud SEEDING CONVECTIVE CLOUDS olympics
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Preweaning period is a critical window for rumen microbial regulation of average daily gain in Holstein heifer calves 被引量:2
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作者 Shengyang Xu Chong Jiao +1 位作者 Qiyu Diao Yan Tu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期396-411,共16页
Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fer... Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fermentation indicators,serum indicators,and growth performance of Holstein heifer calves with different ADG.Twelve calves were chosen from a trail with 60 calves and divided into higher ADG(HADG,high pre-and post-weaning ADG,n=6)and lower ADG(LADG,low pre-and post-weaning ADG,n=6)groups to investigate differences in bacterial composition and functions and host phenotype.Results During the preweaning period,the relative abundances of propionate producers,including g_norank_f_Butyricicoccaceae,g_Pyramidobacter,and g_norank_f_norank_o_Clostridia_vadin BB60_group,were higher in HADG calves(LDA>2,P<0.05).Enrichment of these bacteria resulted in increased levels of propionate,a gluconeogenic precursor,in preweaning HADG calves(adjusted P<0.05),which consequently raised serum glucose concentrations(adjusted P<0.05).In contrast,the relative abundances of rumen bacteria in post-weaning HADG calves did not exert this effect.Moreover,no significant differences were observed in rumen fermentation parameters and serum indices between the two groups.Conclusions The findings of this study revealed that the preweaning period is the window of opportunity for rumen bacteria to regulate the ADG of calves. 展开更多
关键词 Average daily gain CALVES Preweaning period Rumen microbiota
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Influence of 2022 Winter Olympics on Tourism Development of Zhangjiakou City and the Countermeasures
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作者 CHEN Fangying 《Journal of Landscape Research》 2016年第5期97-99,104,共4页
Mega-event is an important driving force for the development of urban tourism industry. As a co-host city of 2022 Winter Olympics, Zhangjiakou will encounter new opportunities in tourism development. This paper build ... Mega-event is an important driving force for the development of urban tourism industry. As a co-host city of 2022 Winter Olympics, Zhangjiakou will encounter new opportunities in tourism development. This paper build a dynamic model about the influence of Olympics on urban tourism industry, and put forward specific strategies for the city promoting its tourism development by taking the opportunity of hosting the Winter Olympics. 展开更多
关键词 Mega event Tourism development 2022 Winter olympics Zhangjiakou
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The neutrophil–osteogenic cell axis promotes bone destruction in periodontitis 被引量:1
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作者 Yutaro Ando Masayuki Tsukasaki +12 位作者 Nam Cong-Nhat Huynh Shizao Zang Minglu Yan Ryunosuke Muro Kazutaka Nakamura Masatsugu Komagamine Noriko Komatsu Kazuo Okamoto Kenta Nakano Tadashi Okamura Akira Yamaguchi Kazuyuki Ishihara Hiroshi Takayanagi 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期154-162,共9页
The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction b... The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune–bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNAsequencing analysis on mouse periodontal lesions and showed that neutrophil–osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk. 展开更多
关键词 period NEUTROPHIL DESTRUCTION
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Ultrafast dynamics of femtosecond laser-induced high spatial frequency periodic structures on silicon surfaces 被引量:3
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作者 Ruozhong Han Yuchan Zhang +6 位作者 Qilin Jiang Long Chen Kaiqiang Cao Shian Zhang Donghai Feng Zhenrong Sun Tianqing Jia 《Opto-Electronic Science》 2024年第3期33-46,共14页
Femtosecond laser-induced periodic surface structures(LIPSS)have been extensively studied over the past few decades.In particular,the period and groove width of high-spatial-frequency LIPSS(HSFL)is much smaller than t... Femtosecond laser-induced periodic surface structures(LIPSS)have been extensively studied over the past few decades.In particular,the period and groove width of high-spatial-frequency LIPSS(HSFL)is much smaller than the diffraction limit,making it a useful method for efficient nanomanufacturing.However,compared with the low-spatial-frequency LIPSS(LSFL),the structure size of the HSFL is smaller,and it is more easily submerged.Therefore,the formation mechanism of HSFL is complex and has always been a research hotspot in this field.In this study,regular LSFL with a period of 760 nm was fabricated in advance on a silicon surface with two-beam interference using an 800 nm,50 fs femtosecond laser.The ultrafast dynamics of HSFL formation on the silicon surface of prefabricated LSFL under single femtosecond laser pulse irradiation were observed and analyzed for the first time using collinear pump-probe imaging method.In general,the evolution of the surface structure undergoes five sequential stages:the LSFL begins to split,becomes uniform HSFL,degenerates into an irregular LSFL,undergoes secondary splitting into a weakly uniform HSFL,and evolves into an irregular LSFL or is submerged.The results indicate that the local enhancement of the submerged nanocavity,or the nanoplasma,in the prefabricated LSFL ridge led to the splitting of the LSFL,and the thermodynamic effect drove the homogenization of the splitting LSFL,which evolved into HSFL. 展开更多
关键词 laser-induced periodic surface structures(LIPSS) local field enhancement collinear pump-probe imaging silicon high spatial frequency periodic structures
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OLYMPICS 北京?大阪?
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作者 根岸智代 《中国商界》 2001年第7期24-24,共1页
2008年奥林匹克在哪儿举办?听说很多城市都提出了在本城市举办的申请。大阪和北京是申奥的城市之一,它们各自所在的国家又是相距很近的一衣带水的邻邦。两国从历史上就一直往来不断,特别是近些年,两国之间的来往更加密切。
关键词 olympics
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London Olympics: Gloomy Economy?
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作者 yang cheng Changsha University, Hunan, China 《China's Foreign Trade》 2012年第7期58-59,共2页
The "Study on the Impact of Olympic Games" issued by the Department for Culture, Media and Sport of Britain in December 2005,
关键词 olympics issued LONDON BRITAIN COMMITTEE trying be
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Standards Serve the Olympics:Building a“Green Olympics”——Forum on Green Olympics and Sustainable Development
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《China Standardization》 2007年第5期36-37,共2页
  On June 26th a forum entitled Green Olympics and Sustainable Development was hosted by the International Organization for Standardization (ISO); Standardization Administration of the People's Republic of China...   On June 26th a forum entitled Green Olympics and Sustainable Development was hosted by the International Organization for Standardization (ISO); Standardization Administration of the People's Republic of China (SAC);Science and Technology Committee for the Games of the ⅩⅩⅨ Olympiad; General Administration of Quality Supervision, Inspection and Quarantine of the PRC (AQSIQ); State Environmental Protection Administration of China; China Meteorological Administration;and the Certification and Accreditation Administration of the PRC at Beijing International Conference Hall.…… 展开更多
关键词 ISO PRC Standards Serve the olympics Forum on Green olympics and Sustainable Development Green olympics
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Wrestling: Glory of India at the Olympics--A Brief History of Indian Wresting Team in the Olympic Games
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作者 Naveen Singh Suhag 《Journal of Sports Science》 2015年第4期195-202,共8页
Wrestling as an Olympic sport has been around since the dawn of modem Olympic games and India is a participating nation in it. Wrestling has unique position among Olympic disciplines in India, from being provider of f... Wrestling as an Olympic sport has been around since the dawn of modem Olympic games and India is a participating nation in it. Wrestling has unique position among Olympic disciplines in India, from being provider of first individual medal to newly independent nation to lately becoming most significant contributor in medal tally. This coming of age of Indian wrestling team with double medal tally in the last Olympics has been outcome of long and steady journey of Indian wrestling team over a period of 40-50 years and numerous Summer Olympic Games. However, this journey of Indian wrestling team in the Olympics is also a stoW of significant twist and turn, near misses and also of glow. So this article covers the entire saga of Indian wrestlers at highest sporting event of world--Olympic Games, from inception of first Indian team of mere three grapplers to latest Olympics with debut of first Indian female grappler in Olympic arena. This history is written by sweat and hard work of Indian grapplers with its own highs and lows. 展开更多
关键词 Indian wrestling team the olympics wrestlers of India in olympic Games freestyle and Greco Roman Wrestling.
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Quality Improvement of Slow Traffic Space in Shijingshan District under the Background of Winter Olympics: A Case Study of Lugu Street of Shijingshan District
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作者 LI Daoyong HE Qilin ZANG Hengyi 《Journal of Landscape Research》 2022年第6期61-63,67,共4页
In the context of the Beijing 2022 Winter Olympics, the quality improvement of slow traffic space in Shijingshan District faces many challenges. Through the exploration of “slow traffic space” and its design concept... In the context of the Beijing 2022 Winter Olympics, the quality improvement of slow traffic space in Shijingshan District faces many challenges. Through the exploration of “slow traffic space” and its design concept and strategy theory, the problem of slow traffic space is sorted out from the aspects of policy background, spatial form and cultural construction, with Lugu Street as an example. Based on the unique cultural resources in the district, the optimization strategies are proposed from the aspects of spatial form improvement, unsupervised technology utilization, enhancement of residents’ willingness to slowly traffic and Winter Olympics culture shaping. In addition, a slow traffic space improvement scheme with easy implementation, convenient access and rich connotation is formed, in order to provide new methods and ideas for improving the quality of slow traffic space. 展开更多
关键词 Beijing Winter olympics Slow traffic space Shijingshan District
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Study on the Impact of Bid for Winter Olympics on the Development of Chinese Winter Sports
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作者 Mingzhu Zhao Tao Liu 《Journal of Sports Science》 2016年第3期175-181,共7页
The 128th plenary session of International Olympic Committee declared on July 31, 2015 after vote that Beijing and Zhan^iakou will be the bidding cities of 2022 Winter Olympics. It was the second time for China to suc... The 128th plenary session of International Olympic Committee declared on July 31, 2015 after vote that Beijing and Zhan^iakou will be the bidding cities of 2022 Winter Olympics. It was the second time for China to successfully bid Olympic Games since 2008 Summer Olympics, which will encourage China to continue to develop sports career in the process of sports power construction and will have long-term construction meanings. Chinese winter sports industry and sports culture will enter into the fast booming development period in the future 7 years. The paper begins with Beijing and Zhangjiakou Winter Olympics bid and the future Chinese winter sports industry construction to illustrate the impact of bid for Winter Olympics on the future winter sports career development. 展开更多
关键词 Winter olympics BID BEIJING Chinese winter sports sports career impact.
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