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44篇 您的检索式:作者名="Keming Li"
    题名 作者 年代 出处 被引量
1ELE restrains empty glumes from developing into lemmas显示文摘Although there is evident homology among reproductive organs when comparing Poaceae (grass) and eudicots, the identity of grass specific organs, such as lodicules, palea, lemma, and glumes has been the subject of a vast and largely inconclusive discussion. Here we provide some direct evidence to support the idea that the empty glumes of rice (Oryza sativa) are counterparts of lemmas. We show that the development of empty glumes is regulated by ELE (elongated empty glume), which belongs to a plant specific novel gene family. Mutations at the ELE locus cause elongated empty glumes, which mimic the lemmas and have the epidermal morphology of lemmas with four or five vascular bundles. As a nuclear-localized gene, ELE is specifically expressed at the empty glumes of immature spikelets, and its ectopic expression causes many floral development defects, including lemma-like palea, extra palea-like structures, elongated lodicules, extra stamens and stigmas. Our result suggests that empty glumes are lemmas of the sterile florets located at the lateral side of the rice spikelet, and ELE acts as a regulator restraining its growth to maintain its small size in wild-type plants.Lilan Hong Qian Qian Keming Zhu Ding Tang Zejun Huang Ling Gao Ming Li Minghong Gu Zhukuan Cheng 2010Journal of Genetics and Genomics2010,37,2:11
2Contrasting elevational diversity patterns for soil bacteria between two ecosystems divided by the treeline显示文摘Above- and below-ground organisms are closely linked, but how elevational distribution pattern of soil microbes shifting across the treeline still remains unknown. Sampling of 140 plots with transect, we herein investigated soil bacterial distribution pattern from a temperate forest up to a subalpine meadow along an elevational gradient using Illumina sequencing. Our results revealed distinct elevational patterns of bacterial diversity above and below the treeline in responding to changes in soil conditions:a hollow elevational pattern in the forest(correlated with soil temperature, pH, and C:N ratio) and a significantly decreasing pattern in the meadow(correlated with soil pH, and available phosphorus). The bacterial community structure was also distinct between the forest and meadow, relating to soil pH in the forest and soil temperature in the meadow. Soil bacteria did not follow the distribution pattern of herb diversity, but bacterial community structure could be predicted by herb community composition. These results suggest that plant communities have an important influence on soil characteristics, and thus change the elevational distribution of soil bacteria. Our findings are useful for future assessments of climate change impacts on microbial community.Guixiang Li Guorui Xu Congcong Shen Yong Tang Yuxin Zhang Keming Ma 2016Science China(Life Sciences)2016,59,11:9
3NDRG4 prevents cerebral ischemia/reperfusion injury by inhibiting neuronal apoptosis显示文摘Cerebral ischemia is a major cause of mortality and long-term morbidity worldwide.NDRG4 has been shown to protect against cerebral ischemia,although the underlying mechanisms remain largely unclear.Here we found that NDRG4 expression was decreased in the brain tissues of ischemia/reperfusion(IR)rats,indicating increased apoptosis rates among cerebral cells.NDRG4 restoration via an adenovirus significantly attenuated cerebral infarct sizes and impairments in IR rats.Furthermore,adenovirus-mediated NDRG4 inhibited cell apoptosis in the brains of IR rats and regulated the expression of Bcl-2,Bax,caspase-3,and c-Fos.Moreover,we found that NDRG4 increased expression of BDNF,which is strongly related to cerebral ischemia and cellular apoptosis.Altogether,our findings demonstrate that NDRG4 protects cerebral IR injury by inhibiting cell apoptosis and regulates cerebral cell apoptosis by increasing BDNF expression.These results suggest that NDRG4 may be a therapeutic target for IR treatment.Lan Wen Lei Liu Linyan Tong Jinfang Li Keming Zhang Qinbin Zhang Changqing Li 2019Genes & Diseases2019,6,4:6
4Joint Beamforming Optimization for Reconfigurable Intelligent Surface-Enabled MISO-OFDM Systems显示文摘In this paper,we investigate the reconfigurable intelligent surface(RIS)-enabled multiple-input-single-output orthogonal frequency division multiplexing(MISO-OFDM)system under frequency-selective channels,and propose a low-complexity alternating optimization(AO)based joint beamforming and RIS phase shifts optimization algorithm to maximize the achievable rate.First,with fixed RIS phase shifts,we devise the optimal closedform transmit beamforming vectors corresponding to different subcarriers.Then,with given active beamforming vectors,near-optimal RIS reflection coefficients can be determined efficiently leveraging fractional programming(FP)combined with manifold optimization(MO)or majorization-minimization(MM)framework.Additionally,we also propose a heuristic RIS phase shifts design approach based on the sum of subcarrier gain maximization(SSGM)criterion requiring lower complexity.Numerical results indicate that the proposed MO/MM algorithm can achieve almost the same rate as the upper bound achieved by the semidefinite relaxation(SDR)algorithm,and the proposed SSGM based scheme is only slightly inferior to the upper bound while has much lower complexity.These results demonstrate the effectiveness of the proposed algorithms.Keming Feng Xiao Li Yu Han Yijian Chen 2021China Communications2021,18,3:6
5Effect of combined medicated thread moxibustion plus needle picking therapy of Zhuang nationality medicine on antioxidant levels in a rat model of sciatica显示文摘OBJECTIVE: To investigate the effect and underlying mechanisms of combined medicated thread moxibustion therapy plus needle picking therapy of Zhuang nationality medicine on antioxidant levels in a rat model of sciatica.METHODS: One hundred Wistar rats, of specific pathogen free level, were randomly divided into five groups: normal control group, model group,medicated thread moxibustion group, needle picking group, and combination group. Each group contained 20 rats. In the model, medicated thread moxibustion, needle picking, and combination groups,sciatica models were established through chronicconstriction injury of the sciatic nerve. After the model was established, the rats in the medicated thread moxibustion, needle picking, and combination groups were given the corresponding therapies for 21 days. The control and model groups received no treatment. Reactive oxygen species, superoxide dismutase, malondialdehyde, and total antioxidant capacity changes were determined.Nicotinamide adenine dinucleotide phosphate(NADPH) oxidase subunit NADPH oxidases 4(NOX4) m RNA expression and the morphology of cells were observed to detect apoptosis of gamma-aminobutyric acid ergic(GABAergic) neurons.RESULTS: Compared with control group, reactive oxygen species and malondialdehyde levels rose significantly in the model group(P < 0.01), while superoxide dismutase and total antioxidant capacity levels were lowered(P < 0.05). Compared with the model group, reactive oxygen species and malondialdehyde decreased in the needle picking group(P < 0.05), while superoxide dismutase levels were increased(P < 0.05); reactive oxygen species and malondialdehyde significantly decreased in the combination group(P < 0.01). In addition, the model group had higher NOX4 m RNA expression than that of the control group(P < 0.05), and the combination group had lower expression levels than that of the model group(P < 0.05). Apoptosis of GABAergic neurons was observed in the model group, and was attenuated after combined therapy.CONCLUSION: The medicated thread moxibustion therapy plus needle picking therapy of Zhuang nationality medicine can prevent oxidative damage in the rat model of sciatica via down-regulating NOX4 expression, improving antioxidant capacity, and in-hibiting the oxidative damage pathway of GABAergic neurons.Tang Hanqing Zheng Jianyu Li Tianzi Li Keming Li Xiaohua Dou Xibin Huang Chunchuan Liang Ye 2016Journal of Traditional Chinese Medicine2016,36,6:4
6Discovery and its geological significance of the mantle- derived helium in the inclusions of the Ordovician oil-bearing reservoir rocks in the Huanghua depression,China显示文摘The values of the helium isotopes in the inclusions of the Ordovician reservoir rocks in the Kongxi buried hill belt in the Huanghua depression were first measured and the source of helium and its geological significance were investigated in comparison with those of the helium isotopes in the conclusions in the Ordovician rocks in the Ordos basin and the Tarim basin. The input of the mantle-derived helium into the inclusions in the carbonate reservoir rocks was found from the Konggu 3 well, the Konggu 4 well, and the Konggu 7 well in the Kongxi buried hill belt. The 3He/4He and R/Ra in the conclusions in the Ordovician oil-bearing reservoir rocks in the Konggu 7 well average 2.54×10-6(3) (sample quantity, the same below) and 1.82(3), respectively. The percent of the mantle-derived helium in the inclusions of the reservoir rocks in the Konggu 7 well reaches up to an average of 23.0%(3). The age of the contribution of the mantle-derived helium to the inclusions in the Kongxi buried hill belt is in the Late Triassic or the Early Tertiary. The finding of the mantle-derived helium shows that the interaction of the deep crust with mantle and the activity of deep faults occurred, the terrestrial heat flow value was high, and mantle-derived inorganic gas pools might be formed in the Kongxi buried hill belt. The finding of the mantle-derived helium in the inclusions of oil-bearing reservoir rocks also provides a new way for researching the activity of mantle-derived matter and its associated geological problems.ZHANG Xiaobao XU Yongchang SUN Mingliang CHENG Keming LIU Wenhui LI Xiufen MA Liyuan 2004Science China Earth Sciences2004,47,1:4
7The geometric simulation and analysis of the blind growth fold in the overthrust belt of the southern section of the frontier Longmen Mt.during Late Triassic显示文摘The seismic profiles processed by high-resolution display that a blind growth fault-bend fold emerges in depth of seismic exploration area in Dayi in the southern section of the frontier Longmen Mt.This paper presents a detailed structural interpretation to seismic section,then describes the deformed geometry related to the pre-growth strata,the growth strata and the post-growth strata on both limbs of the fold.The computer geometric simulation,based on the model of fault-bend fold,is utilized to stimulate the geometry of the blind growth fold at different sedimentation rates in Dayi.These structural features are subsequently extracted and compared with the actual seismic reflection section.Our research suggests that a low angle overthrust formed during Late Triassic also appears in the southern section of the frontier Longmen Mt.The event of structure took place at the depositional stage of a portion of the middle and upper fourth member of Xujiahe Formation(T3x4),which corresponds to thrusting in the northern section of the frontier Longmen Mt.However,the thrusting displacement here is smaller than one of the northern section.CHEN Wei YANG KeMing LI ShuBin JIAN GaoMing TANG Jin ZHAO Yiao SU Qian 2009Chinese Science Bulletin2009,54,8:3
8Analysis of single frequency modulation for passive hydrogen maser显示文摘Based on the theory of the passive hydrogen maser,along with the technology of frequency modulation and modulation transfer spectroscopy, the theoretical expression of the single frequency modulation for the passive hydrogen maser and the function of the cavity and H line error signals separation are derived, which are basically coincident with the experiment. The absorption and dispersion spectrum curves with different resonance widths show that the cavity and hydrogen transition serve as discriminators, and the two error signals can be separated.Through the calculations of the two error signals in the passive hydrogen maser, it analyzes the traditional method of the two error signals separation, and then describes a new improved method for the passive hydrogen servo loops consisting in the use of a single modulation frequency and frequency discrimination. A null interaction of the two error signals for the new selection of the phase setting is deduced theoretically and validated by the simulation.The preliminary experimental result confirms the feasibility of this new approach, which can reduce the influence from the cavity frequency variety on the crystal oscillator and contribute significantly to the long term performance of the passive hydrogen maser.Hefei Zheng Jing Li Wenming Wang Lianshan Gao Keming Feng 2017Journal of Systems Engineering and Electronics2017,28,4:2
9The study of methanol aromatization on transition metal modified ZSM-5 catalyst显示文摘In this article, transition metals of Cu, La and Zn were used as adjuvant to prepare modified HZSM-5 by impregnation method. The catalysts were characterized by XRD, BET, NH_3-TPD and Py-IR to reveal the microstructure and acid property. The catalysis performances of methanol aromatization of catalysts were investigated in a fixed-bed reactor. The results show that the strength and distribution of acid center of these catalysts are significantly influenced by the species of transition metal. There are more mediate strong Lewis acid center in Zn modified HZSM-5 catalyst and therefore exhibits higher selectivity to aromatic, benzene, toluene and xylenes in the MTA reaction..Keming Ji Jiayao Xun Ping Liu Qingwen Song Junhua Gao Kan Zhang Jingyuan Li 2018Chinese Journal of Chemical Engineering2018,26,9:2
10Hydrocarbon Generation and Expulsion of the Upper Triassic T3x5Source Rocks in the Western Sichuan Depression: Assessment for Unconventional Natural Gas显示文摘Tight-sand gas in the Jurassic and shale gas within the fifth member of Xujiahe Formation(T3x5) in the Western Sichuan Basin(WSD) are currently regarded as the most prolific emerging unconventional gas plays in China. This study conducted a conventional evaluation of T3x5 source rocks in the WSD, and investigated their hydrocarbon generation and expulsion characteristics, including intensity, efficiency and amount. The results show that, the T3x5 source rocks are thick(generally >200 m), and have a high total organic content(TOC), ranging from 2.5 to 4.5 wt%. It is thus indivative of a great hydrocarbon generation potential when they underwent high thermal evolution(Ro>1.2%) in the area. In addition, an improved method of hydrocarbon generation potential is applied, indicating that the source rocks reached a hydrocarbon expulsion threshold with vitrinite reflectance(Ro) reaching 1.06%, and that the comprehensive hydrocarbon expulsion efficiency is about 60%. The amount of hydrocarbon generation and expulsion from T3x5 source rocks is 3.14×1010 t and 1.86×1010 t, respectively, with a residual amount of 1.28×1010 t within them. Continuous-type tight-sand gas is predicted to have developed in the Jurassic in the Chengdu Sag of the WSD because of the good source-reservoir configuration; the Jurassic sandstone reservoirs are tight, and the gas expelled from the T3x5 source rocks migrates for very short distances vertically and horizontally. The amount of gas accumulation in the Jurassic reservoirs derived from T3x5 source rocks is up to 9.3×108 t. Geological resources of shale gas are up to 1.05×1010 t. Small differences between the amounts calculated by the volumetric method and those obtained by hydrocarbon generation potential method may be due to other gas accumulations present within interbedded sands associated with gas shales.GUO Yingchun SONG Yan PANG Xiongqi WANG Youwei YANG Keming LI Boyuan 2015Acta Geologica Sinica(English Edition)2015,89,1:2
11Application of chaos mind evolutionary algorithm in antenna arrays synthesis显示文摘Liu Jianxia Li Nan Xie Keming 2010J of Computers2010,5,5:1
12The chitinase gene (Bbchit1) from Beauveria bassiana enhances resistance to Cytospora chrysosperma in Populus tomentosa Carr.显示文摘Zhichun Jia Yimin Sun Li Yuan Qiaoyan Tian Keming Luo 2010Biotechnology Letters2010,,9:1
13The effect of option trading显示文摘This paper studies the effect of option trading on corporate investment and financing policies.Based on prior literature,I hypothesize that option market induces informed trading and thus reduces information asymmetry and the cost of capital.As a result,firms with high option trading have more investment and financing.Specifically,based on the United States public data,this paper finds that option trading volume increases corporate investment and financing,but reduces cash holdings and corporate payouts.These results are robust to the inclusion of industry or firm fixed effect,a control for endogenous options trading,and the use of alternative measures of option trading and corporate policies.The effect of option trading is stronger for firms with higher information asymmetry problems.Finally,this paper finds the results are inconsistent with the“quiet Life”hypothesis and the catering hypothesis.Keming Li 2021Financial Innovation2021,7,1:1
14An improved procedure for Agrobacterium-mediated transformation of trifoliate orange (Poncirus trifoliata L. Raf.) via indirect organogenesis显示文摘Xiuping Zou Demou Li Xiaoying Luo Keming Luo Yan Pei 2008In Vitro Cellular & Developmental Biology - Plant2008,,3:1
15Extraction and antioxidant activities of intracellular polysaccharide from Pleurotus sp. mycelium显示文摘Xiaonan Liu Bo Zhou Rongshan Lin Le Jia Peng Deng Keming Fan Guoyi Wang Li Wang Jianjun Zhang 2010International Journal of Biological Macromolecules2010,,2:1
16Influenza virus vaccine expressing fusion and attachment protein epitopes of respiratory syncytial virus induces protective antibodies in BALB/c mice显示文摘Chengrong Bian Shuzhen Liu Na Liu Guangzhou Zhang Li Xing Yingwei Song Yueqiang Duan Hongjing Gu Ya Zhou Peirui Zhang Zhiwei Li Keming Zhang Zhaohai Wang Shaogeng Zhang Xiliang Wang Penghui Yang 2014Antiviral Research2014,,:1
17Copper Removal from Molten Steel by Gasification显示文摘A novel method is proposed to enhance the gasification and removal of copper from molten steel by adding ammonium salts or urea into molten steel under normal pressure.The decopperization experiments were conducted in a molybdenum-wire resistance furnace at 1 873 K.The copper content of about 400 g of a mild steel was reduced from 0.49%(mass fraction,the same below) and 0.51% to 0.31% and 0.38% using 0.7 g of NH_4C1 and 0.5 g of(NH_4)_2C_2O_4 respectively,while the copper content of the molten steel was reduced from 0.61%to 0.56% using 2.00 g of NH_2CONH_2.Li Liansheng Li Shiqi Xiang Changxiang Cao Jie Liu Keming Li Suqin 1999Journal of Iron and Steel Research(International)1999,6,2:1
18Long non-coding RNA Loc554202 regulates proliferation and migration in breast cancer cells显示文摘Yongguo Shi Jianwei Lu Jing Zhou Xueming Tan Ye He Jie Ding Yun Tian Li Wang Keming Wang 2014Biochemical and Biophysical Research Communications2014,,:1
19Creation of macroporous calcium phosphate cements as bone substitutes by using genipin-crosslinked gelatin microspheres显示文摘Meng Li Xingyan Liu Xudong Liu Baofeng Ge Keming Chen 2009Journal of Materials Science: Materials in Medicine2009,,4:1
20Designing regional pattern for ecosystem restoration:A case study显示文摘Designing regional pattern is challenging for ecosystem restoration both in theory and in practice. The present study proposed a new approach to design regional pattern for ecosystem restoration with a case in the arid valley of Upper Minjiang River, SW China. The procedures are: (1) Determine the regional pattern of main environmental factors based on the relationships between the important environmental factors and the main geographical factors generated from DEM data. (2) Overlay the maps of the main environmental factors. (3) Generate a lookup table according to the species selection rule we proposed to link the candidate restoration species to the main environmental factors.(4) Determine the regional pattern of ecosystem restoration by positioning the restoration species in the map of environmental factors according to the lookup table. The regional restoration pattern designed in this way would be applicable not only to restoring a region, but also to predicting the future landscape change.LI Guoqiang , MA Keming, FU Bojie & LIU Shiling State Key Lab of Systems Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China School of Environmental Sciences, Beijing Normal University, Beijing 100875, China 2006Science China(Technological Sciences)2006,49,z1:1
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