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Observation of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and study of the P-wave DsDs mesons
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作者 麦迪娜 M.N.Achasov +143 位作者 S.Ahmed M.Albrecht M.Alekseev A.Amoroso 安芬芬 安琪 白羽 O.Bakina R.Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 范荆州 方建 房双世 方易 R.Farinelli L.Fava F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾珊 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad 纪全 姬清平 季晓斌 季筱璐 姜侯兵 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L. 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期5-16,共12页
Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with ... Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined. 展开更多
关键词 cross section P-WAVE D_s MESONS resonance parameters spin-parity BESIII
Evidence for the decays of ∧c^+→∑^+η and ∑^+η’
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作者 麦迪娜 M.N.Achasov +146 位作者 S.Ahmed M.Albrecht M.Aleksee A.Amoroso 安芬芬 安琪 白羽 O.Bakina R. Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 O.Cakir A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈平亮 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 段鹏飞 范荆州 方建 房双世 方易 R.Farinelli L.Fava S.Fegan F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 T.Hussain N.Hu sken W.Ikegami Andersson M.Irshad 纪全 姬清平 季晓斌 季筱璐 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson A.Julin N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kornicer M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kuhn J.S.Lange P.Larin L.La 《中国物理C:英文版》 SCIE CAS CSCD 2019年第8期15-23,共9页
We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII col... We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII collider. We find evidence for the decays ∧^+→∑^+η and ∑^+η' and with statistical significance of and , respectively. Normalizing to the reference decays ∧^+→∑^+π^0 and ∑^+ω, we obtain the ratios of the branching fractions B(∧C^+→∑^+η)/V(∧^→∑^+π^0)and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)to be and , respectively. The upper limits at the 90% confidence level are set to be B(∧C^→∑^+η)/V(∧^+→∑^+π^0)<0.58 and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)<1.2. Using BESIII measurements of the branching fractions of the reference decays, we determine B(∧C^+→∑^+η)=(0.41±019±0.05)%(<0.68%) and B(∧C^+→∑^+η)=(1.34+0.53+0.19)%(<1.9%). Here, the first uncertainties are statistical and the second systematic. The obtained branching fraction of ∧C^+→∑^+η is consistent with the previous measurement, and the branching fraction of ∧C^+→∑^+η is measured for the first time. 展开更多
关键词 charmed BARYON ∧c^+ DECAYS branching FRACTIONS
Oncogenic osteomalacia caused by a phosphaturic mesenchymal tumor of the femur:A case report 预览
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作者 Dong Tang Xiao-Man Wang +1 位作者 Yong-Sheng Zhang Xiao-Xiao Mi 《世界临床病例杂志》 2019年第15期2081-2086,共6页
BACKGROUND Oncogenic osteomalacia caused by phosphaturic mesenchymal tumors is very difficult to detect.We report a case of tumor-induced osteomalacia caused by a phosphaturic mesenchymal tumor of the left femur in a ... BACKGROUND Oncogenic osteomalacia caused by phosphaturic mesenchymal tumors is very difficult to detect.We report a case of tumor-induced osteomalacia caused by a phosphaturic mesenchymal tumor of the left femur in a middle-aged woman after medical imaging and biopsy.CASE SUMMARY A 57-year-old woman presented with progressive bone pain for five years.She was diagnosed with hypophosphatemic osteomalacia,as her laboratory data showed low serum phosphorus and low serum calcium.Her knee joint radiography revealed an osteolytic lesion of the left femur.A computed tomography scan showed mixed density shadows in the left femur.Magnetic resonance imaging of the left femur showed the presence of an oval area with a hypointense signal in T1-weighted magnetic resonance imaging(MRI)and highlow mixed signal in T2-weighted MRI.Biopsy samples revealed the presence of short spindle cells,vascularization,and characteristics of phosphaturic mesenchymal tumors.Tumor resection was performed,and the clinical presentations and laboratory abnormalities were reversed.CONCLUSION Diagnosis of oncogenic osteomalacia is difficult due to the varieties and localization of source tumors and absence of pathognomonic biomedical signs.Our case highlights the importance of a combination of medical imaging and biopsy in the diagnosis of oncogenic osteomalacia caused by a phosphaturic mesenchymal tumor. 展开更多
关键词 Oncogenic OSTEOMALACIA Phosphaturic MESENCHYMAL tumor HYPOPHOSPHATEMIA HYPOCALCEMIA Case report
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Standardized Operational Protocol for Human Brain Banking in China
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作者 Wenying Qiu Hanlin Zhang +18 位作者 Aimin Bao Keqing Zhu Yue Huang Xiaoxin Yan Jing Zhang Chunjiu Zhong Yong Shen Jiangning Zhou Xiaoying Zheng Liwei Zhang Yousheng Shu Beisha Tang Zhenxin Zhang Gang Wang Ren Zhou Bing Sun Changlin Gong Shumin Duan Chao Ma 《神经科学通报:英文版》 SCIE CAS CSCD 2019年第2期270-276,共7页
With the progress of society, there is an increasing need to tackle disorders of the central nervous system. Human brain tissue, unlike animal tissues, is an irreplaceable resource for the study of neurological diseas... With the progress of society, there is an increasing need to tackle disorders of the central nervous system. Human brain tissue, unlike animal tissues, is an irreplaceable resource for the study of neurological diseases (1)Aimed at scientific research and education, the roles of human brain tissue repositories are to acquire brain tissue from donors, prepare, process, and preserve collected samples,provide tissue to specific eligible facilities, and determine the characteristics of each tissue sample. 展开更多
关键词 Standardized BRAIN BANKING INCREASING
NIR-II fluorescence in vivo confocal microscopy with aggregation-induced emission dots
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作者 Wenbin Yu Bing Guo +7 位作者 Hequn Zhang Jing Zhou Xiaoming Yu Liang Zhu Dingwei Xue Wen Liu Xianhe Sun Jun Qian 《科学通报:英文版》 SCIE EI CSCD 2019年第6期410-416,共7页
Significantly reduced tissue scattering of fluorescence signals in the second near-infrared(NIR-Ⅱ,1,000–1,700 nm)spectral region offers opportunities for large-depth in vivo bioimaging.Nowadays,most reported works c... Significantly reduced tissue scattering of fluorescence signals in the second near-infrared(NIR-Ⅱ,1,000–1,700 nm)spectral region offers opportunities for large-depth in vivo bioimaging.Nowadays,most reported works concerning NIR-II fluorescence in vivo bioimaging are realized by wide-field illumination and 2D-arrayed detection(e.g.,via InGaAs camera),which has high temporal resolution but limited spatial resolution due to out-of-focus signals.Combining NIR-II fluorescence imaging with confocal microscopy is a good approach to achieve high-spatial resolution visualization of biosamples even at deep tissues.In this presented work,a NIR-II fluorescence confocal microscopic system was setup.By using a kind of aggregation-induced emission(AIE)dots as NIR-II fluorescent probes,800 lm-deep 3D in vivo cerebrovascular imaging of a mouse was obtained,and the spatial resolution at 700 lm depth could reach 8.78 lm.Moreover,the time-correlated single photon counting(TCSPC)technique and femtosecond laser excitation were introduced into NIR-II fluorescence confocal microscopy,and in vivo confocal NIR-II fluorescence lifetime microscopic imaging(FLIM)of mouse cerebral vasculature was successfully realized. 展开更多
关键词 Confocal microscopy NIR-II FLUORESCENCE AIE DOTS In vivo cerebrovascular IMAGING TCSPC FLIM IMAGING
Superconductivity, electronic phase diagram, and pressure effect in Sr1-xPrxFBiS2
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作者 Wei You Lin Li +8 位作者 HaiYang Yang JiaLu Wang HongYing Mao Li Zhang ChuanYing Xi Jie Cheng YongKang Luo JianHui Dai YuKe Li 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第5期99-106,共8页
Based on a combination of X-ray diffraction, electrical transports, magnetic susceptibility, specific heat, and pressure-effect measurements, we report the results of experiments on a series of BiS2-based Sr1-xPrxFBiS... Based on a combination of X-ray diffraction, electrical transports, magnetic susceptibility, specific heat, and pressure-effect measurements, we report the results of experiments on a series of BiS2-based Sr1-xPrxFBiS2 superconductors with the maximum Tcof 2.7 K for x=0.5 and at ambient pressure. Superconductivity appears only for 0.4≤x≤0.7 whereas the normal-state resistivity shows the semiconducting-like behaviors. The magnetic susceptibility χ(T) displays the low superconducting shielding volume fractions and C(T) shows no distinguishable anomaly near Tc, which suggests a filamentary superconductivity in the Pr-doped polycrystalline samples. By varying doping concentrations, an electronic phase diagram is established. Upon applying pressure on the optimally doped Sr0.5Pr0.5FBiS2 system, Tcis abruptly enhanced, reaches 8.5 K at the critical pressure of Pc=1.5 GPa, and increases slightly to 9.7 K at 2.5 GPa. Accompanied by the enhancement of superconductivity from the low-to the high-Tc phases, the normal state undergoes a semiconductor-to-metal transition when under pressure. This scenario may be linked to enhanced overlap of the Bi-6 p and S-p orbitals, which contributes to the enhanced superconductivity above Pc. The pressuretemperature phase diagram for Sr0.5Pr0.5FBiS2 is also presented. 展开更多
关键词 BiS2-based SUPERCONDUCTORS SUPERCONDUCTIVITY PHASE DIAGRAM pressure effect
Correlates of extinction risk in Chinese endemic birds 预览
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作者 Chuanwu Chen Di Zeng +3 位作者 Yuhao Zhao Yiru Wu Junfeng Xu Yanping Wang 《鸟类学研究:英文版》 CSCD 2019年第2期101-110,共10页
Background: China has a relative high degree of endemism of birds due to its large area, diversified topography, and varied climates and habitats. Among the 77 Chinese endemic birds, 29 species are classified as threa... Background: China has a relative high degree of endemism of birds due to its large area, diversified topography, and varied climates and habitats. Among the 77 Chinese endemic birds, 29 species are classified as threatened according to the officially released China Biodiversity Red List in 2015. Chinese endemic birds should be the focus of conservation because their local extinction in China means complete global extinction. However, to date, no study has explicitly examined the patterns and processes of extinction and threat in Chinese endemic birds. Methods: We obtained eleven biological traits and four extrinsic factors that are commonly hypothesized to influence extinction risk. After phylogenetic correction, these factors were used separately and in combination to assess their associations with extinction risk. Results: We found that 37.7% of Chinese endemic birds were listed as threatened (Vulnerable, Endangered and Critically Endangered). Small range size, high hunting vulnerability, and high human population density were important predictors of high extinction risk in Chinese endemic birds. Conclusions: Our study is the first to systematically investigate the patterns and processes of extinction risk in Chinese endemic birds. We suggest that endemic species with small range size and living in area with high human densities require conservation priorities. Conservation efforts should also focus on the reduction of human threats, such as human hunting and habitat degradation, for the effective preservation of Chinese endemic birds. 展开更多
关键词 Comparative analysis ENDEMIC BIRDS GEOGRAPHIC range size Human population density HUNTING vulnerability PROACTIVE conservation Red list
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Global, regional, and cladistic patterns of variation in climatic niche breadths in terrestrial elapid snakes
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作者 Long-Hui Lin Xia-Ming Zhu +2 位作者 Yu Du Meng-Chao Fang Xiang Ji 《动物学报:英文版》 SCIE CAS CSCD 2019年第1期1-9,共9页
We obtai ned geo-refere need occurre nee and climatic data from in dividual localities for 59 species of terrestrial elapid snakes, used phylogenetic generalized least squares regression to investigate spatial and cla... We obtai ned geo-refere need occurre nee and climatic data from in dividual localities for 59 species of terrestrial elapid snakes, used phylogenetic generalized least squares regression to investigate spatial and cladistic patter ns of variation in climatic niche breadths, and compared patter ns within and across regions and clades to see if they parallel or differ from each other. Specifically, we test (1) whether a species' climatic niche breadth on a given niche axis relates to its position along that axis, and to its climatic niche breadth on another niche axis, and (2) whether variation in niche breadths among species is explained by within-locality variation in climatic conditions or by among-locality variation. We found that:(1) there is an overall global patter n, and patter ns in individual regi ons or clades gen erally parallel each other and global patter ns;(2) species in wanner environments have narrower temperature niche breadths (TNBs);(3) precipitation niche breadth (PNB) and position are positively related;⑷ TNB and PNB are not related;and ⑸ within-locality variation in climatic conditions explains most variation in TNBs, whereas among-locality variation explains most variation in PNBs. Our results are consistent with those reported for lizards of the families Phrynosomatidae and Varanidae, con firm the importance of withi n-locality n iche breadth to species n iche breadth, and show a more im porta nt role of amon g-locality n iche breadth in affecting species niche breadth in terrestrial elapids than in lizards. 展开更多
关键词 climate ELAPIDAE NICHE BREADTH NICHE position NICHE variance precipitation temperature
One-step implementation of a multi-target-qubit controlled phase gate with cat-state qubits in circuit QED
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作者 You-Ji Fan Zhen-Fei Zheng +2 位作者 Yu Zhang Dao-Ming Lu Chui-Ping Yang 《物理学前沿:英文版》 SCIE CSCD 2019年第2期13-21,共9页
We propose a single-step implementation of a muti-target-qubit controlled phase gate with one catstate qubit (cqubit) simultaneously controlling n — 1 target cqubits. The two logic states of a c.qubit are represented... We propose a single-step implementation of a muti-target-qubit controlled phase gate with one catstate qubit (cqubit) simultaneously controlling n — 1 target cqubits. The two logic states of a c.qubit are represented by two orthogonal cat states of a single cavity mode. In this proposal, the gate is implemented with n microwave cavities coupled to a superconducting transnion qutrit. Because the qutrit remains in the ground state during the gate operation, decoherence caused due to the qutrit5s energy relaxation and dephasing is greatly suppressed. The gate implementation is quite simple because only a single-stcp operation is needed and neither classical pulse nor measurement is required. Numerical simulations demonstrate that high-fidelity realization of a controlled phase gate with one cqubit simultaneously con trolling two targe t cqubits is feasible with present circuit QED technology. This proposal can be extended to a wide range of physical systems to realize the proposed gate, such as multiple microwave or optical cavities coupled to a natural or artificial three-level atom. 展开更多
关键词 circuit QED cat-state multi-target-qubit controlled phase gate
RESTplus: an improved toolkit for resting-state functional magnetic resonance imaging data processing
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作者 Xi-Ze Jia Jue Wang +6 位作者 Hai-Yang Sun Han Zhang Wei Liao Ze Wang Chao-Gan Yan Xiao-Wei Song Yu-Feng Zang 《科学通报:英文版》 SCIE EI CSCD 2019年第14期953-954,共2页
Resting-state functional magnetic resonance imaging (RS-fMRI)[1,2] provides relatively high spatial and temporal resolution for mapping spontaneous brain activity non-invasively. It has been widely used in cognitive n... Resting-state functional magnetic resonance imaging (RS-fMRI)[1,2] provides relatively high spatial and temporal resolution for mapping spontaneous brain activity non-invasively. It has been widely used in cognitive neuroscience and clinical studies. A number of comprehensive software packages have been developed for RS-fMRI data analysis, among which a MATLAB package named REST (RESing-state fMRI data analysis Toolkit, released in October 2008 at http://www.restfmri.net)[3] is the earliest one dedicated to RS-fMRI analysis. REST focuses on RS-fMRI postprocessing metrics. 展开更多
关键词 RESTING-STATE functional magnetic RESONANCE IMAGING (RS-fMRI) REST MATLAB
Holocene aeolian stratigraphic sequences in the eastern portion of the desert belt(sand seas and sandy lands) in northern China and their palaeoenvironmental implications
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作者 Xiaoping YANG Peng LIANG +11 位作者 Deguo ZHANG Hongwei LI Patrick RIOUAL Xulong WANG Bing XU Zhibang MA Qianqian LIU Xiaozong REN Fangen HU Yuxin HE Gang RAO Ninghua CHEN 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第8期1302-1315,共14页
This paper presents the environmental history and its responses to palaeoclimatic changes since the start of the Holocene in the eastern portion of the desert belt(sand seas and sandy lands) in northern China by compa... This paper presents the environmental history and its responses to palaeoclimatic changes since the start of the Holocene in the eastern portion of the desert belt(sand seas and sandy lands) in northern China by comparing the aeolian sandpalaeosol sequences and their palaeoclimatic proxies. The optically stimulated luminescence(OSL) ages of the aeolian sandpalaeosol sedimentary sequences and a series of palaeoenvironmental proxies show that:(1) The large-scale dune landscape currently in the Kubuqi Sand Sea was formed during the Holocene in general;and the palaeosol was generally developed during the period of 4–2 ka, indicating conditions favorable for vegetation growth, soil development, and organic carbon accumulation due to increased precipitation or effective moisture and weakened aeolian activities;the large-scale expansion of dunes in the recent 2 ka is closely linked to human activities. The variable discharge of the Yellow River with diversions for irrigation may have resulted in a more consistent supply of aeolian particles for dune field expansion.(2) The dune landscape of the Hunshandake Sandy Land was likely formed around 12 ka, and before this, the western part of the Hunshandake Sandy Land would have been covered by a single large lake;it was obviously wetter than today in the sandy land during the period of 9.6–3 ka and the palaeosols were developed at the same time. But the aeolian activities have not been completely dormant in this long-lasting wetter epoch;because the Holocene wetter period was likely time-transgressive across the region.(3) The palaeosol of the Hulunbuir Sandy Land began to develop as early as 14.5 ka, probably continuing until the last 2 ka. The palaeosol development of various dune fields in the eastern portion of the desert belt(sand seas and sandy lands) in northern China is spatially heterogeneous, and even the palaeosol development time in different locations within each sandy land is inconsistent. During the middle Holocene(especially the 7.5–3.5 ka), all the sand 展开更多
关键词 SAND sea SANDY land Environmental evolution Kubuqi Hunshandake Hulunbuir
Identifying Intraspecific Variation in Venom Yield of Chinese Cobra(Naja atra) from Ten Populations in Mainland China
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作者 Jianfang GAO Yin YIN +4 位作者 Yanfu QU Jin WANG Longhui LIN Hongliang LU Xiang JI 《亚洲两栖爬行动物研究:英文版》 SCIE CSCD 2019年第1期32-40,共9页
Detailed information on venom yield is helpful in preparing antivenoms and treating snakebites, but such information is lacking for many species of venomous snakes. The Chinese cobra(Naja atra) is a large sized, venom... Detailed information on venom yield is helpful in preparing antivenoms and treating snakebites, but such information is lacking for many species of venomous snakes. The Chinese cobra(Naja atra) is a large sized, venomous snake commonly found in southeastern China, where it causes a heavy burden of snakebites. To examine the effects of various factors(morphology, sex, age, season, and geographical origin) on the venom yield in this snake, we collected venom samples of 446 individuals(426 adults and 20 neonates) from 10 populations of N. atra over an eightyear period. We used two variables, lyophilized venom mass(venom yield) and solid content of venom(% solids), to quantify the venom yield. We used linear regression analysis to check if venom yield was related to morphological factors, one-way ANOVA and one-way ANCOVA to detect the sexual, ontogenetic, and geographic variation in venom yield, and repeated-measures ANOVA to examine seasonal shifts in venom yield. Our results indicate that venom yield of N. atra is positively related to the morphological traits examined, with male snakes expelling more venom than females. Venom yield in N. atra was age-related, with elder snakes always expelling more venom than younger ones. Geographic variation in venom yield was also observed, while seasonal variation was not. The solid content of venom was lower in males than in females, but this was not related to morphology, season, age, or geography. Our findings suggest that venom yield in N. atra is influenced by multiple factors, as well as by the interactions among these factors. 展开更多
关键词 Naja atra VENOM YIELD INTRASPECIFIC variation SNAKEBITE
Alleviation by abscisic acid of Al toxicity in rice bean is not associated with citrate efflux but depends on ABI5-mediated signal transduction pathways
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作者 Wei Fan Jia Meng Xu +6 位作者 Pei Wu Zhi Xin Yang He Qiang Lou Wei Wei Chen Jian Fen Jin Shao Jian Zheng Jian Li Yang 《植物学报:英文版》 SCIE CAS CSCD 2019年第2期140-154,共15页
Under conditions of aluminum(Al) toxicity,which severely inhibits root growth in acidic soils, plants rapidly alter their gene expression to optimize physiological fitness for survival. Abscisic acid(ABA) has been sug... Under conditions of aluminum(Al) toxicity,which severely inhibits root growth in acidic soils, plants rapidly alter their gene expression to optimize physiological fitness for survival. Abscisic acid(ABA) has been suggested as a mediator between Al stress and gene expression, but the underlying mechanisms remain largely unknown. Here,we investigated ABA-mediated Al-stress responses, using integrated physiological and molecular biology approaches.We demonstrate that Al stress caused ABA accumulation in the root apex of rice bean(Vigna umbellata [Thunb.] Ohwi &Ohashi), which positively regulated Al tolerance. However,this was not associated with known Al-tolerance mechanisms. Transcriptomic analysis revealed that nearly one-third of the responsive genes were shared between the Al-stress and ABA treatments. We further identified a transcription factor, ABI5, as being positively involved in Al tolerance. Arabidopsis abi5 mutants displayed increased sensitivity to Al, which was not related to the regulation of AtALMT1 and AtMATE expression. Functional categorization of ABI5-mediated genes revealed the importance of cell wall modification and osmoregulation in Al tolerance, a finding supported by osmotic stress treatment on Al tolerance. Our results suggest that ABA signal transduction pathways provide an additional layer of regulatory control over Al tolerance in plants. 展开更多
关键词 Alleviation by abscisic acid of Al toxicity in rice bean IS not associated with CITRATE EFFLUX BUT depends on ABI5-mediated sign ABA Figure ABI
Quantum Fisher information width in quantum metrology
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作者 Bo Liu GuoLong Li +2 位作者 YanMing Che Jie Chen XiaoGuang Wang 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第4期29-37,共9页
In scenarios of quantum metrology, the unitary parametrization process often depends on space directions. How to characterize the sensitivity of parameter estimation to space directions is a natural question. We propo... In scenarios of quantum metrology, the unitary parametrization process often depends on space directions. How to characterize the sensitivity of parameter estimation to space directions is a natural question. We propose the concept of the quantum Fisher information (QFI) width, which is the difference between the maximum and minimum values of the QFI, to quantitatively study the sensitivity. We find that Fock states, the bosonic coherent states, and the displaced Fock states all have zero widths, indicating that QFI is completely inert over all directions, while the width for the spin state with all spins down or up is equal to the number of particles, so this concept will enable us to choose appropriate directions to make unitary transformation to obtain larger QFI. The QFI width of the displaced quantum states is found to be independent of the magnitude of the displacement for both spin and bosonic systems. We also find some relations between the QFI width and squeezing parameters. 展开更多
关键词 QUANTUM METROLOGY QUANTUM FISHER INFORMATION QUANTUM FISHER INFORMATION WIDTH
Macroecological Patterns of Climatic Niche Breadth Variation in Lacertid Lizards
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作者 Mengchao FANG Xiaming ZHU +2 位作者 Yu DU Lin ZHANG Longhui LIN 《亚洲两栖爬行动物研究:英文版》 SCIE CSCD 2019年第1期41-47,共7页
Measuring climatic niche position and breadth may help to determine where species can occur over space and time. Using GIS-based and phylogenetic comparative methods, we investigated global patterns of variation in cl... Measuring climatic niche position and breadth may help to determine where species can occur over space and time. Using GIS-based and phylogenetic comparative methods, we investigated global patterns of variation in climatic niche breadth in lacertid lizards to test the following three hypotheses about climatic niche widths. First, does a species’ temperature or precipitation niche breadth relate to its temperature or precipitation niche position(the mean value of annual mean temperature or annual precipitation across sampled localities in the range of each species)? Second, are there trade-offs between a species’ temperature niche breadth and precipitation niche breadth? Third, does a species’ temperature or precipitation niche breadth relate to altitude or latitude? We expect that:(1) species distributed in cold regions are specialized for low-temperature environments(i.e. narrow niche breadth center around low temperatures);(2) a negative relationship between species niche breadth on temperature and precipitation axes according to the tradeoff hypothesis(i.e. species that tolerate a broad range of precipitation regimes cannot also tolerate a broad range of temperatures);(3) precipitation niche breadth decreases with altitude or latitude, whereas temperature climatic niche breadth increases with altitude or latitude. Based on the analytical results we found that:(1) temperature niche breadth and position are negatively related, while precipitation niche breadth and position are positively related;(2) there is no trade-off between temperature and precipitation niche breadths;and (3) temperature niche breadth and latitude/altitude are positively related, but precipitation niche breadth and latitude/altitude are not significantly related. Our results show many similarities with previous studies on climatic niche widths reported for amphibians and lizards, which provide further evidence that such macroecological patterns of variation in climatic niche breadths may be widespread. 展开更多
关键词 Macroecological pattern CLIMATIC NICHE BREADTH CLIMATIC NICHE POSITION LACERTIDAE
Deeply pipelined interpolation architecture for full ultra-HD H.265/HEVC video encoding 预览
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作者 丁丹丹 Gui Kai +2 位作者 Ye Xin Liu Fuchang Pan Zhigeng 《高技术通讯:英文版》 CAS 2019年第1期28-34,共7页
Fractional motion estimation (FME) improves the video encoding efficiency significantly. However, its high computational complexity limits the real-time processing capability. Therefore, it is a key problem to reduce ... Fractional motion estimation (FME) improves the video encoding efficiency significantly. However, its high computational complexity limits the real-time processing capability. Therefore, it is a key problem to reduce the implementation complexity of FME, especially in hardware design. This paper presents a novel deeply pipelined interpolation architecture of FME for the real-time realization of H.265/HEVC full Ultra-HD video encoder. First, a pipelined interpolation architecture together with an elegant processing order is proposed to deal with different search positions in parallel without pipeline stall and data conflict. Second, interpolation results sharing strategies are exploited among search positions to reduce the memory cost. Finally, the structure of the interpolation filter is further optimized for an area efficient implementation. As a result, the proposed design costs 41 917 slice LUTs on the Xilinx Kintex-7 FPGA platform with a 308 MHz working frequency. The measured throughput reaches a record of 1.238 Gpixels/s, which is sufficient for the real-time encoding of 8192×4320@ 30fps video. 展开更多
关键词 fractional motion estimation (FME) INTERPOLATION pipeline H.265/HEVC full Ultra-HD
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RFES:一种面向移动Web3D的实时火灾逃生系统(英文)
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作者 Feng-ting YAN Yong-hao HU +3 位作者 Jin-yuan JIA Qing-hua GUO He-hua ZHU Zhi-geng PAN 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2019年第8期1061-1075,共15页
基于Web3D构建公共消防疏散系统存在许多限制其计算能力的瓶颈。本文集中解决3个关键问题:(1)大型建筑场景数据量大,难以通过互联网传输并在网络终端设备实现可视化;(2)原始火灾动态模拟器烟气数据量大,且实时动态变化,难以通过互联网... 基于Web3D构建公共消防疏散系统存在许多限制其计算能力的瓶颈。本文集中解决3个关键问题:(1)大型建筑场景数据量大,难以通过互联网传输并在网络终端设备实现可视化;(2)原始火灾动态模拟器烟气数据量大,且实时动态变化,难以通过互联网传输并在网络终端设备实现可视化;(3)为公众提供的智能消防疏散系统往往难以兼顾准确性和实时性。针对以上问题,本文提出3个解决方案:(1)将大型场景模型简化为轻量型场景模型;(2)将动态烟雾简化为轻量级烟雾模型;(3)利用场景模型和烟雾数据建立动态障碍物图,规划最优疏散路径。本文提出一种基于蚁群优化算法(RFES-ACO)的实时消防疏散系统,该算法基于动态信息素重用。仿真结果表明,公众可在移动Web3D设备上实时、顺畅地进行消防疏散演练的交互和体验。最后,与leader-follower算法和随机算法的对比实验,证明了实时消防疏散系统(RFES)的高效性,其疏散率优于其它两种算法。 展开更多
关键词 消防疏散演习 建筑信息建模建筑空间 移动Web3D 基于蚁群优化算法的实时消防疏散系统
Double-authentication-preventing signatures revisited:new definition and construction from chameleon hash
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作者 Fei LI Wei GAO +2 位作者 Gui-lin WANG Ke-fei CHEN Chun-ming TANG 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2019年第2期176-186,共11页
Double-authentication-preventing signature(DAPS) is a novel signature notion proposed at ESORICS2014. The double-authentication-preventing property means that any pair of signatures on two different messages with the ... Double-authentication-preventing signature(DAPS) is a novel signature notion proposed at ESORICS2014. The double-authentication-preventing property means that any pair of signatures on two different messages with the same subject will result in an immediate collapse of the signature system. A few potential applications of DAPS have been discussed by its inventors, such as providing a kind of self-enforcement to discourage certificate authority(CA) from misbehaving in public key infrastructure and offering CA some cryptographic arguments to resist legal coercion. In this study, we focus on some fundamental issues on DAPS. We propose a new definition,which is slightly weakened but still reasonable and strong enough to capture the DAPS concept. We develop the new notion of invertible chameleon hash functions with key exposure. Then we propose a generic DAPS scheme, which is provably secure if the underlying invertible chameleon hash function with key exposure is secure. We instantiate this general construction to obtain the DAPS schemes respectively based on the well-known assumptions of integer factorization, Rivest-Shamir-Adleman(RSA), and computational Diffie-Hellman(CDH). They are more efficient than previous DAPS schemes. Furthermore, unlike previous constructions, the trusted setup condition is not needed by our DAPS schemes based on RSA and CDH. 展开更多
关键词 Double-authentication-preventing SIGNATURES CHAMELEON HASH function Digital signature Provable security AUTHORITY trust level
Spatiotemporal distribution of seasonal bird assemblages on land-bridge islands:linking dynamic and static views of metacommunities 预览
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作者 Chuanwu Chen Marcel Holyoak +2 位作者 Yanping Wang Xingfeng Si Ping Ding 《鸟类学研究:英文版》 CSCD 2019年第3期250-261,共12页
Background: Although assessing temporal dynamics of populations is crucial for understanding metacommunities, empirical studies have primarily analyzed only static snapshots of communities. Here, we present a holistic... Background: Although assessing temporal dynamics of populations is crucial for understanding metacommunities, empirical studies have primarily analyzed only static snapshots of communities. Here, we present a holistic view of how species traits and habitat characteristics relate to metacommunity dynamics and use it to test for differences in the spatiotemporal distribution of seasonal bird assemblages. Methods: We surveyed forest birds in breeding and winter seasons within 36 islands for 9 years. We then grouped birds into four landbird assemblages, selected on the basis of published differences in biology or ecology: winter residents, migratory winter visitors, breeding summer residents, and migratory summer visitors. We estimated dynamic species colonization and extirpation through the 9-year period, and evaluated the associations among island attributes, species attributes and community composition. Results: Overall, winter and summer residents showed strong associations between composition and habitat structure of the islands. In addition, winter and summer residents on large islands had lower extirpation and turnover than winter and summer visitors. Visitor assemblages showed no significant habitat associations, and in winter had high extirpation rates and small body sizes. By contrast, local extirpation of summer visitors was correlated with local species richness, indicating a likely effect of competition on extirpation. Conclusions: Our results demonstrated repeated patterns among species composition, bird traits, habitat/island characteristics and observed metacommunity dynamics. Winter and summer residents best matched species sorting and patch dynamics, respectively, due to differences in resource availability and requirements of overwinter survival versus breeding. Summer visitors were consistent with species sorting and winter visitors were randomly distributed, likely because of interactions with resident competitors. Our results highlight that coexisting seasonal migrant and resident assemblages di 展开更多
关键词 Body size COLONIZATION Competition EXTIRPATION Island TURNOVER METACOMMUNITY
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An efficient iO-based data integrity verification scheme for cloud storage
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作者 Lixue SUN Chunxiang XU +1 位作者 Yuan ZHANG Kefei CHEN 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第5期237-239,243共4页
Dear editor,With the advent of big data,an increasing number of people are storing their data on remote cloud servers.Cloud storage services enable users to flexibly maintain and access their data via mobile or wirele... Dear editor,With the advent of big data,an increasing number of people are storing their data on remote cloud servers.Cloud storage services enable users to flexibly maintain and access their data via mobile or wireless networks.However,despite these benefits,cloud storage deprives users of physical control over their data,which poses new challenges in data security(1–4)Data integrity protection is one of the most important of these security chal-lenges. 展开更多
关键词 TPA An EFFICIENT iO-based data integrity VERIFICATION SCHEME for cloud storage
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