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3855篇 您的检索式:作者名="Yang Cui"
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1Human umbilical cord Wharton's Jelly-derived mesenchymal stem cells differentiation into nerve-like cells显示文摘Background The two most basic properties of mesenchymal stem cells (MSCs) are the capacities to self-renew indefinitely and differentiate into multiple cells and tissue types. The cells from human umbilical cord Wharton’s Jelly have properties of MSCs and represent a rich source of primitive cells. This study was conducted to explore the possibility of inducing human umbilical cord Wharton’s Jelly-derived MSCs to differentiate into nerve-like cells.Methods MSCs were cultured from the Wharton’s Jelly taken from human umbilical cord of babies delivered after full-term normal labor. Salvia miltiorrhiza and β-mercaptoethanol were used to induce the human umbilical cord-derived MSCs to differentiate. The expression of neural protein markers was shown by immunocytochemistry. The induction process was monitored by phase contrast microscopy, electron microscopy (EM), and laser scanning confocal microscopy (LSCM) .The pleiotrophin and nestin genes were measured by reverse transcription-polymerase chain reaction (RT-PCR). Results MSCs in the Wharton’s Jelly were easily attainable and could be maintained and expanded in culture. They were positive for markers of MSCs, but negative for markers of hematopoietic cells and graft-versus-host disease (GVHD)-related cells. Treatment with Salvia miltiorrhiza caused Wharton’s Jelly cells to undergo profound morphological changes. The induced MSCs developed rounded cell bodies with multiple neurite-like extensions. Eventually they developed processes that formed networks reminiscent of primary cultures of neurons. Salvia miltiorrhiza and β-mercaptoethanol also induced MSCs to express nestin, β-tubulinⅢ, neurofilament (NF) and glial fibrillary acidic protein (GFAP). It was confirmed by RT-PCR that MSCs could express pleiotrophin both before and after induction by Salvia miltiorrhiza. The expression was markedly enhanced after induction and the nestin gene was also expressed.Conclusions MSCs could be isolated from human umbilical cord Wharton’s Jelly. They were capable of differentiating into nerve-like cells using Salvia miltiorrhiza or β-mercaptoethanol. The induced MSCs not only underwent morphologic changes, but also expressed the neuron-related genes and neuronal cell markers. They may represent an alternative source of stem cells for central nervous system cell transplantation.MA Lian FENG Xue-yong CUI Bing-lin Frieda Law JIANG Xue-wu YANG Li-ye XIE Qing-dong HUANG Tian-hua 2005Chinese Medical Journal2005,,23:103
2Stable classi?cation with limited sample: transferring a 30-m resolution sample set collected in 2015 to mapping 10-m resolution global land cover in 2017显示文摘As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, environmental pollution, and ultimately human health, timely and higher resolution land cover information is urgently needed to achieve the sustainable development goals of the United Nations.Peng Gong Han Liu Meinan Zhang Congcong Li Jie Wang Huabing Huang Nicholas Clinton Luyan Ji Wenyu Li Yuqi Bai Bin Chen Bing Xu Zhiliang Zhu Cui Yuan Hoi Ping Suen Jing Guo Nan Xu Weijia Li Yuanyuan Zhao Jun Yang Chaoqing Yu Xi Wang Haohuan Fu Le Yu Iryna Dronova Fengming Hui Xiao Cheng Xueli Shi Fengjin Xiao Qiufeng Liu Lianchun Song 2019Science Bulletin2019,64,6:166
3A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
4RNA-seq analysis of prostate cancer in the Chinese population identifies recurrent gene fusions, cancer-associated long noncoding RNAs and aberrant alternative splicings显示文摘在有前列腺癌症的不同赛跑的病人之中有显著不同;然而,位于这差别下面的机制仍然保持不清楚。这里,我们在场 transcriptome 的一处全面风景用 RNA-seq,越过关于基因熔化的前列腺癌症 transcriptomes 的揭示巨大的差异,长 noncoding RNA (长 ncRNA ) ,其他的拼接和体的变化从中国人口 14 主要前列腺癌症和他们的配对的正常对应物介绍。14 个肿瘤(21.4%) 中的三个在中国病人怀有 TMPRSS2 尔格熔化,和这熔化的低流行进一步在一个另外的肿瘤集合(10/54=18.5%) 被证实。尤其是,二新奇基因熔化, CTAGE5-KHDRBS3 (20/54=37%) 和 USP9Y-TTTY15 (19/54=35.2%) ,在我们的耐心的队经常发生了。介绍的进一步系统的 transcriptional 识别了是在肿瘤表示的差别的众多的长 ncRNAs。在长 ncRNA 和基因的表示之间的关联的分析建议长 ncRNAs 可以在 transcriptional 规定以外有功能。这研究在中国人口产出新卓见进前列腺癌症的致病。Shancheng Ren Zhiyu Peng Jian-Hua Mao Yongwei Yu Changjun Yin Xin Gao Zilian Cui Jibin Zhang Kang Yi Weidong Xu Chao Chen Fubo Wang Xinwu Guo Ji Lu Jun Yang Min Wei Zhijian Tian Yinghui Guan Liang Tang Chuanliang Xu Linhui Wang Xu Gao Wei Tian Jian Wang Huanming Yang Jun Wang Yinghao Sun 2012Cell Research2012,22,5:66
5H7N9 virulent mutants detected in chickens in China pose an increased threat to humans显示文摘Jianzhong Shi Guohua Deng Huihui Kong Chunyang Gu Shujie Ma Xin Yin Xianying Zeng Pengfei Cui Yan Chen Huanliang Yang Xiaopeng Wan Xiurong Wang Liling Liu Pucheng Chen Yongping Jiang Jinxiong Liu Yuntao Guan Yasuo Suzuki Mei Li Zhiyuan Qu Lizheng Guan Jinkai Zang Wenli Gu Shuyu Han Yangming Song Yuzhen Hu Zeng Wang Linlin Gu Wenyu Yang Libin Liang Hongmei Bao Guobin Tian Yanbing Li Chuanling Qiao Li Jiang Chengjun Li Zhigao Bu Hualan Chen 2017Cell Research2017,27,12:70
6Transmission Dynamics of an Outbreak of the COVID-19 Delta Variant B.1.617.2——Guangdong Province,China,May-June 2021显示文摘On May 21,2021,a local case of coronavirus disease 2019(COVID-19)was confirmed in a 75-year-old woman(experienced onset of symptoms on May 18)in Liwan District,Guangzhou City,Guangdong Province,China.The number of infections has increased in the following 10 days and led to 5 generations of transmission.Meng Zhang Jianpeng Xiao Aiping Deng Yingtao Zhang Yali Zhuang Ting Hu Jiansen Li Hongwei Tu Bosheng Li Yan Zhou Jun Yuan Lei Luo Zimian Liang Youzhi Huang Guoqiang Ye Mingwei Cai Gongli Li Bo Yang Bin Xu Ximing Huang Yazun Cui Dongsheng Ren Yanping Zhang Min Kang Yan Li 2021China CDC weekly2021,3,27:51
7Chinese expert consensus on cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal malignancies显示文摘Locoregional spread of abdominopelvic malignant tumors frequently results in peritoneal carcinomatosis(PC). The prognosis of PC patients treated by conventional systemic chemotherapy is poor, with a median survival of < 6 mo. However, over the past three decades, an integrated treatment strategy of cytoreductive surgery(CRS) + hyperthermic intraperitoneal chemotherapy(HIPEC) has been developed by the pioneering oncologists, with proved efficacy and safety in selected patients. Supported by several lines of clinical evidence from phases Ⅰ, Ⅱ and Ⅲ clinical trials, CRS + HIPEC has been regarded as the standard treatment for selected patients with PC in many established cancer centers worldwide. In China, an expert consensus on CRS + HIPEC has been reached by the leading surgical and medical oncologists, under the framework of the China Anti-Cancer Association. This expert consensus has summarized the progress in PC clinical studies and systematically evaluated the CRS + HIPEC procedures in China as well as across the world, so as to lay the foundation for formulating PC treatment guidelines specific to the national conditions of China.Yan Li Yun-Feng Zhou Han Liang Hua-Qing Wang Ji-Hui Hao Zheng-Gang Zhu De-Seng Wan Lun-Xiu Qin Shu-Zhong Cui Jia-Fu Ji Hui-Mian Xu Shao-Zhong Wei Hong-Bin Xu Tao Suo Shu-Jun Yang Cong-Hua Xie Xiao-Jun Yang Guo-Liang Yang 2016World Journal of Gastroenterology2016,22,30:58
8The ages of U-Pb and Sm-Nd for eclogite from the western segment of Altyn Tagh tectonic belt——Evidence for existence of Caledonian orogenic root显示文摘The eclogites of Altyn Tagh tectonic belt occur as lens within gneisses characterized by amphibolite-facies mineral parageneses. The well-preserved eclogite is selected for Sm-Nd and U-Pb isotopic dating. The Sm-Nd isotopic data yield a whole rock-garnet-omphacite isochron of (500 ?10) Ma. The U-Pb isotopic measurements of zircons show that the fourJianxin Zhang Zeming Zhang Zhiqin Xu Jingsui Yang Junwen Cui 1999Chinese Science Bulletin1999,44,24:46
9Transplantation of UC-MSCs on collagen scaffold activates follicles in dormant ovaries of POF patients with long history of infertility显示文摘Premature ovarian failure(POF) is a refractory disease for clinical treatment with the goal of restoring fertility. In this study,umbilical cord mesenchymal stem cells on a collagen scaffold(collagen/UC-MSCs) can activate primordial follicles in vitro via phosphorylation of FOXO3 a and FOXO1. Transplantation of collagen/UC-MSCs to the ovaries of POF patients rescued overall ovarian function, evidenced by elevated estradiol concentrations, improved follicular development, and increased number of antral follicles. Successful clinical pregnancy was achieved in women with POF after transplantation of collagen/UC-MSCs or UC-MSCs. In summary, collagen/UC-MSC transplantation may provide an effective treatment for POF.Lijun Ding Guijun Yan Bin Wang Lu Xu Yan Gu Tong Ru Xiaoying Cui Lei Lei Jingyu Liu Xiaoqiang Sheng Bin Wang Chunxue Zhang Yanjun Yang Ruiwei Jiang Jianjun Zhou Na Kong Feifei Lu Huaijun Zhou Yannan Zhao Bing Chen Yali Hu Jianwu Dai Haixiang Sun 2018Science China(Life Sciences)2018,61,12:43
10Anatomical and chemical characteristics associated with lodging resistance in wheat显示文摘Anatomical and chemical characteristics of stems affect lodging in wheat(Triticum aestivum L.) cultivars. Traits associated with lodging resistance, such as plant height, stem strength, culm wall thickness, pith diameter, and stem diameter, were extensively investigated in earlier studies. However, the solid stem trait was rarely considered. In this study, we measured a range of anatomical and chemical characteristics on solid and hollow stemmed wheat cultivars. Significant correlations were detected between resistance to lodging and several anatomical features, including width of mechanical tissue, weight of low internodes, and width of stem walls. Morphological features that gave the best indication of improved lodging resistance were increased stem width, width of mechanical tissue layer, and stem density. Multiple linear regression analysis showed that 99% of the variation in lodging resistance could be explained by the width of the mechanical tissue layer, suggesting that solid stemmed wheat has several anatomical features for increasing resistance to lodging. In addition, microsatellite markers GWM247 and GWM340 were linked to a single solid stem QTL on chromosome 3BL in a population derived from the cross Xinongshixin(solid stem)/Line 3159(hollow stem). These markers should be valuable in breeding wheat for solid stem.Eryan Kong Dongcheng Liu Xiaoli Guo Wenlong Yang Jiazhu Sun Xin Li Kehui Zhan Dangqun Cui Jinxing Lin Aimin Zhang 2013The Crop Journal2013,1,1:43
11Programmable time-domain digital-coding metasurface for non-linear harmonic manipulation and new wireless communication systems显示文摘Optical non-linear phenomena are typically observed in natural materials interacting with light at high intensities, and they benefit a diverse range of applications from communication to sensing. However,controlling harmonic conversion with high efficiency and flexibility remains a major issue in modern optical and radio-frequency systems. Here, we introduce a dynamic time-domain digital-coding metasurface that enables efficient manipulation of spectral harmonic distribution. By dynamically modulating the local phase of the surface reflectivity, we achieve accurate control of different harmonics in a highly programmable and dynamic fashion, enabling unusual responses, such as velocity illusion. As a relevant application, we propose and realize a novel architecture for wireless communication systems based on the time-domain digital-coding metasurface, which largely simplifies the architecture of modern communication systems, at the same time yielding excellent performance for real-time signal transmission. The presented work, from new concept to new system, opens new pathways in the application of metamaterials to practical technology.Jie Zhao Xi Yang Jun Yan Dai Qiang Cheng Xiang Li Ning Hua Qi Jun Chen Ke Guo Dong Bai Shuo Liu Shi Jin Andrea Alù Tie Jun Cui 2019National Science Review2019,6,2:46
12L-forms of H. pylori显示文摘AIM: To study the occurrence of L-forms of H. pyloriinfection in patients with peptic ulcers and its association with possible changes of cellular immune function in the patients.METHODS: Endoscopic biopsy specimens of gastric antrum and gastric corpus were taken from 228 patients with peptic ulcers and inoculated into Skirrow selective medium for H.pylorivegetative forms and special medium for H. pylori Lforms, followed by bacterial isolation and identification. And peripheral venous blood of the patients was taken to detect the percentage of CD3+, CD4+ and CD8+ with biotin-streptavidin (BSA) and the level of IL-2, IL-6 and IL-8 with ElISA.RESULTS: (1) The detection rates of H. pyloriL-forms and vegetative forms in the patients were 50.88 % (116/228)and 64.91 % (148/228) respectively, and the co-infection rate of H. pyloriL-forms and vegetative forms was 78.38 % (116/148). To be more exact, the detection rates of H. pylori L-forms in male and female patients were 57.04 % (77/135) and 41.94 % (39/93) respectively, and statistics found significant difference between them (P<0.05). Furthermore, the detection rates of H. pyloriL-forms in patients aged 14 years-, 30 years-, 40 years- and 50 years- were 31.91%(15/47), 42.86 % (24/56), 56.94 % (41/72) and 67.92 %(36/53) respectively, and there was significant difference between them (P<0.011). (2) The percentages of CD3+, CD4+,CD8+, the ratio of CD4+/CD8+, and the level of IL-2, IL-6,IL-8 in H. pylori-positive patients were (52.59±5.44) %,(35.51±5.74) %, (27.77±8.64) %, (1.56±0.51), (2.66±0.47)mg/L, (108.62±5.85) ng/L and (115.79±7.18) ng/Lrespectively, compared with those in H. pylori-negative patients, the percentages of CD3+, CD4+ and the ratio of CD4+/CD8+ decreased, but the level of IL-2, IL-6 increased, and the difference was significant (P<0.001-P<0.011).Moreover, the percentages of CD3+, CD4+, CD8+, the ratio of CD4+/CD8+, and the level of IL-2, IL-6, IL-8 in the patients with mixed infection of bothH. pyloriL-forms and vegetative forms were (51.69±5.28) %, (34.75±5.89) %, (27.15±7.45) %, (1.48±0.47), (2.16±0.38) mg/L, (119.45±5.44) ng/L and (123.64±6.24) ng/L respectively, compared with those in patients with simple infection of H. pylorivegetative forms,the percentage of CD4+, the ratio of CD4+/CD8+ and the level of IL-2 increased, but the level of IL-6 and IL-8decreased, statistical difference was found between them (P<0.001-P<0.05).CONCLUSION: L-forms variation often occurs in patients with peptic ulcers who are infected byH. pylori, which is commonly found in male patients and related to ages. The L-forms variation of H. pylori can be an important factor causing disorder of cellular immune function in the patients with peptic ulcers who are infected by H. pylori.Ke-Xia Wang Chao-Pin Li Yu-Bao Cui Ye Tian Qing-Gui Yang School of Medicine, Anhui University of Science & Technology Huainan 232001, Anhui Province, China 2003World Journal of Gastroenterology2003,9,3:47
13The Sequence of Magmatic-Tectonic Events and Orogenic Processes of the Yanshan Belt, North China显示文摘This paper emphasizes that the interactive constraints of geology and isotopic dating is the best approach to construct the geological event sequence, and has compiled 106 data of reasonable isotopic ages for the igneous rocks of the Yanshan belt. We propose a sequence of mgmatic-tectonic events in the Jurassic-Cretaceous Yanshan orogen of North China. Five orogenic episodes are divided, (1) pre-and initial orogenic episode (Early Jurassic); (2) early orogenic episode (Middle Jurassic); (3) peak orogenic episode (Late Jurassic); (4) late orogenic episode (early Early Cretaceous),and (5) post-orogenic episode. Each episode is a short cycle, all of the orogenic processes construct a longer cycle, and they, in general, followed a counter-clockwise (ccw) PTt path. Finally, it is suggested that the Yanshanian movement was so intensive that the magmatism and tectonic deformation had involved all the lithosphere thickness and the lateAchaean-formed cratonic lithosphere had been significantly reworked.DENG Jinfu, SU Shangguo, MO Xuanxue, ZHAO Guochun, XIAO Qinghiu, JI Guangyi,QIU Ruizhao, ZHAO Hailing, LUO Zhaohua, WANG Yang and LIU Cui China University of Geosciences, Beijing 100083 and Key Laboratory of Lithospheric Tectonics and Lithoprobe Techniques, Ministry of Education of China 2004Acta Geologica Sinica(English Edition)2004,78,1:35
14Degradation of corn stalk by the composite microbial system of MC1显示文摘MC1 的合成微生物引起的系统被用来降级玉米秸以便象 MC1 的细菌的作文一样决定降级的产品的性质。结果显示发酵肉汤的 pH 典型地代表由 MC1 的木质纤维素降级,在早阶段减少并且在降级的以后的阶段增加。微生物引起的生物资源在在降级以后的日子 3 上达到顶点。MC1 高效地降级了在将近 70% 的玉米秸在哪个期间它的纤维素内容在 71.2% 减少了,在 76.5% 的半纤维素和在 24.6% 的木质素。在发酵肉汤的水溶性的糖类(WSC ) 的内容在开始的三天期间日益增多地增加了,并且此后减少了,建议在降级过程的早阶段的 WSC 的累积。各种各样的不稳定的产品的全部的层次在降级以后在第三天内达到顶点,并且不稳定的产品的 7 种类型在发酵肉汤被检测。这些是乙醇,醋酸, 1,2-ethanediol, propanoic 酸, butanoic 酸, 3-methyl-butanoic 酸和甘油。六主要混合物是分析的份量上,每混合物的内容是乙醇(0.584 g/L ) ,醋酸(0.735 g/L ) , 1,2-ethanediol (0.772 g/L ) , propanoic 酸(0.026 g/L ) , butanoic 酸(0.018 g/L ) 和甘油(4.203 g/L ) 。基于 DNA 的 16S rDNA PCR-DGGE 分析,从文化答案收集的细菌的房间的描述证明在 MC1 的细菌的社区的作文从以前的研究与观察基本上与一致。这显示 MC1 的结构在不同木质纤维素材料的降级期间是很稳定的。GUO Peng WANG Xiaofen ZHU Wanbin YANG Hongyan CHENG Xu CUI Zongjun 2008Journal of Environmental Sciences2008,20,1:39
15Limbic Encephalitis Associated with Anti-y-aminobutyric Acid B Receptor Antibodies: A Case Series from China显示文摘Hong-Zhi Guan Hai-Tao Ren Xun-Zhe Yang Qiang Lu Bin Peng Yi-Cheng Zhu Xiao-Qiu Shao Yong-Qiang Hu Dong Zhou Li-Ying Cui 2015Chinese Medical Journal2015,,22:38
16Anisotropic coding metamaterials and their powerful manipulation of differently polarized terahertz waves显示文摘Metamaterials based on effective media can be used to produce a number of unusual physical properties(for example,negative refraction and invisibility cloaking)because they can be tailored with effective medium parameters that do not occur in nature.Recently,the use of coding metamaterials has been suggested for the control of electromagnetic waves through the design of coding sequences using digital elements‘0’and‘1,'which possess opposite phase responses.Here we propose the concept of an anisotropic coding metamaterial in which the coding behaviors in different directions are dependent on the polarization status of the electromagnetic waves.We experimentally demonstrate an ultrathin and flexible polarization-controlled anisotropic coding metasurface that functions in the terahertz regime using specially designed coding elements.By encoding the elements with elaborately designed coding sequences(both 1-bit and 2-bit sequences),the x-and y-polarized waves can be anomalously reflected or independently diffused in three dimensions.The simulated far-field scattering patterns and near-field distributions are presented to illustrate the dual-functional performance of the encoded metasurface,and the results are consistent with the measured results.We further demonstrate the ability of the anisotropic coding metasurfaces to generate a beam splitter and realize simultaneous anomalous reflections and polarization conversions,thus providing powerful control of differently polarized electromagnetic waves.The proposed method enables versatile beam behaviors under orthogonal polarizations using a single metasurface and has the potential for use in the development of interesting terahertz devices.Shuo Liu Tie Jun Cui Quan Xu Di Bao Liangliang Du Xiang Wan Wen Xuan Tang Chunmei Ouyang Xiao Yang Zhou Hao Yuan Hui Feng Ma Wei Xiang Jiang Jiaguang Han Weili Zhang Qiang Cheng 2016Light(Science & Applications)2016,5,1:36
17Starch grain analysis reveals function of grinding stone tools at Shangzhai site, Beijing显示文摘Prehistoric groundstone tools including slabs (metate, mo-pan) and mullers (mano, mo-bang) are often considered to be tools that were used to process cereals in ancient China. Most archaeologists believe that groundstone tools are indicators of an agrarian economy. This study employed starch grain analysis to examine a slab and a muller excavated from the Shangzhai Site (7500-7000 cal a BP), Beijing. Identifiable starch grains recovered from the stone tools were classified into 9 genera and 12 species, most of which were from acorns and foxtail millets. Remains from the oak species Q. mongolicus, Q. acuttssima, and Q. dentate were identified as well as a few starch grains from broomcorn (Panicum miliaseum) and bean (Vigna sp.). Other starch grains were from unidentifiable roots and grasses. A variety of starch grains indicates that the grinding stone tools were used to process not only cereals, but also other seeds or roots that had to be ground or husked, thus bringing into question the aforementioned cereal hypothesis. Because the numbers of starch grains from nuts and millets were so large, both gathering and cultivation might have been important economic patterns before 7000 years ago in Beijing area. Moreover, the starch remains are derived from plants that indicate that the paleoclimate of Beijing was wetter and warmer than today’s.YANG XiaoYan YU JinCheng Lü HouYuan CUI TianXing GUO JingNing GE QuanSheng 2009Science China Earth Sciences2009,52,8:32
18Prediction of Debris-flow Danger Area by Combining Hydrological and Inundation Simulation Methods显示文摘Debris flows have caused serious human casualties and economic losses in the regions strongly affected by the Ms8.0 Wenchuan earthquake of 2008. Debris flow mitigation and risk assessment is a key issue for reconstruction.The existing methods of inundation simulation are based on historical disasters and have no power of prediction.The rain-flood method can not yield detailed flow hydrograph and does not meet the need of inundation simulation. In this paper,the process of water flow was studied by using the Arc-SCS model combined with hydraulic method,and then the debris flow runoff process was calculated using the empirical formula combining the result from Arc-SCS.The peak discharge and runoff duration served as input of inundation simulation. Then,the dangerous area is predicted using kinematic wave method and Manning equation.Taking the debris flow in Huashiban gully in Beichuan County,Sichuan Province,China on 24 Sep.2008 as example,the peak discharge of water flow and debris flow were calculated as 35.52 m3·s-1 and 215.66 m3·s-,with error of 4.15%compared to the measured values.The simulated area of debris-flow deposition was 161,500 m2,vs.the measured area of 144,097 m2,in error of 81.75%.The simulated maximum depth was 12.3 m,consistent with the real maximum depth between 10 and 15 m according to the field survey.The minor error is mainly due to the flow impact on buildings and variations in cross-section configuration.The present methodology can be applied to predict debris flow magnitude and evaluate its risk in other watersheds inthe earthquake area.CUI Peng 2011Journal of Mountain Science2011,8,1:31
19Discovery of eclogite at northern margin of Qaidam Basin,NW China显示文摘Eclogite was first discovered at the northern margin of the Qaidam Basin in this study. It occurs as pods in the gneiss sequence of Middle to Upper Proterozoic age and is mainly composed of garnet, omphacite, phengite and rutile. The garnets contain 44%-62% of almandine, 15%-33% of grossular and 12%-30% of pyrope molecules, and the omphacites contain 40%-46% of jadeite. Applying garnet_clinopyroxene thermometry and jadeite geobarometry, the peak conditions of eclogite facies metamorphism occurred at about (722±123)℃ and at the pressure of up to c. 22 ×10 8 Pa.Jingsui Yang Zhiqin Xu Haibing Li Cailai Wu Junwen Cui Jianxin Zhang Wen Chen 1998Chinese Science Bulletin1998,43,20:34
20Broadband diffusion of terahertz waves by multi-bit coding metasurfaces显示文摘The terahertz region is a special region of the electromagnetic spectrum that incorporates the advantages of both microwaves and infrared light waves.In the past decade,metamaterials with effective medium parameters or gradient phases have been studied to control terahertz waves and realize functional devices.Here,we present a new approach to manipulate terahertz waves by using coding metasurfaces that are composed of digital coding elements.We propose a general coding unit based on a Minkowski closed-loop particle that is capable of generating 1-bit coding(with two phase states of 0 and 180°),2-bit coding(with four phase states of 0,90°,180°,and 270°),and multi-bit coding elements in the terahertz frequencies by using different geometric scales.We show that multi-bit coding metasurfaces have strong abilities to control terahertz waves by designing-specific coding sequences.As an application,we demonstrate a new scattering strategy of terahertz waves—broadband and wide-angle diffusion—using a 2-bit coding metasurface with a special coding design and verify it by both numerical simulations and experiments.The presented method opens a new route to reducing the scattering of terahertz waves.Li-Hua Gao Qiang Cheng Jing Yang Shao-Jie Ma Jie Zhao Shuo Liu Hai-Bing Chen Qiong He Wei-Xiang Jiang Hui-Feng Ma Qi-Ye Wen Lan-Ju Liang Biao-Bing Jin Wei-Wei Liu Lei Zhou Jian-Quan Yao Pei-Heng Wu Tie-Jun Cui 2015Light(Science & Applications)2015,4,1:31
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