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Periodicity of Retzius lines in fossil Pongo from South china

chinese Science Bulletin 2012年第7期57卷 790-794页

作者： HU Rong1,2,3. ZHAO LingXia1,2 & WU XinZhi2 1 Key laboratory of Evolutionary Systematics of Vertebrates, institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, {3. 100044, china 2 laboratory of Human Evolution, institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, {3. 100044, china 3.Graduate University of chinese academy of sciences, {3. 100049, china laboratory of Human Evolution Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China

Periodicity of Retzius lines is a key factor in dental development. In this study, we examined the periodicity of Retzius lines in fossil Pongo from South china using polarized light microscope observation of dental ground sections. The periodicities all of the 15 teeth were 9 d. Comparisons of periodicity were made with extant primates, fossil apes and hominins. Periodicity of fossil Pongo from South china was relatively long but fell within the variation of extant Pongo, Gorilla and modern human, and longer than periodicity of Pan and other extant primates. Fossil Pongo from South china was similar to Lufengpithecus and Sivapithecus, shorter than Gigantopithecus and longer than European and African fossil apes and most early hominins in periodicity. Generally, the periodicities of Asian large-body fossil apes were longer than the periodicities of European and African large-body fossil apes in Miocene. Difference among species and trend of evolution in periodicity were analyzed and discussed. We found that periodicity might gradually increase from Proconsul in early Miocene to several fossil apes in Miocene and then Gigantopithecus in Pleistocene. In addition, this study made correlate analysis between periodicity and body mass respectively in males and females of six extant apes and five fossil apes, and found that periodicity positively correlated with body mass.

关键词：周期性变化中国南方大猩猩化石灵长类动物早中新世类人猿显微镜观察

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Effects of cosmological constant on motion of UHECR particles

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Science china(Physics,mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe institute of High Energy Physics, chinese academy of sciences, beijing 10003.,{3. Graduate School of chinese academy of sciences, beijing 10003.,{3. institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant A (> 0). Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented here. By solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.

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Uncertainty in magnetic activity indices

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Science china(Technological sciences) 2008年第10期51卷 1659-1664页

作者： XU WenYao institute of Geology and Geophysics, chinese academy of sciences, beijing 100029,{3. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Magnetic activity indices are widely used in theoretical studies of solar-terrestrial coupling and space weather prediction. However, the indices suffer from various uncertainties, which limit their application and even mislead to incorrect conclu-sion. In this paper we analyze three most popular indices, Kp, AE and Dst. Three categories of uncertainties in magnetic indices are discussed: "data uncertainty" originating from inadequate data processing, "station uncertainty" caused by in-complete station covering, and "physical uncertainty" stemming from unclear physical mechanism. A comparison between magnetic disturbances and related indices indicate that the residual Sq will cause an uncertainty of 1―2 in K meas-urement, the uncertainty in saturated AE is as much as 50%, and the uncertainty in Dst index caused by the partial ring currents is about a half of the partial ring cur-rent.

关键词： magnetic activity indices Kp AE Dst solar-terrestrial coupling space weather

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Phylogeny of fireflies (Coleoptera: Lampyridae) inferred from mitochondrial 16S ribosomal DNA, with references to morphological and ethological traits

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Progress in Natural Science:Materials International 2006年第8期16卷 817-826页

作者： LI Xueyan, YANG Shuang, XIE Meng and LIANG Xingcai (laboratory of Entomology, Kunming institute of Zoology, chinese academy of sciences, Kunming 650223.{3. Key laboratory of Cellular and Molecular Evolution, Kunming institute of Zoology, chinese academy of sciences, Kunming 650223.{3. Graduate School of the chinese academy of sciences, beijing 10003.,{3.) [a]laboratory of Entomology Kunming Institute of Zoology Chinese Academy of Sciences Kunming China [b]Graduate School of the chinese academy of sciences Beijing China [c]Key laboratory of Cellular and Molecular Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming China

We sequenced partial mitochondrial 16S ribosomal DNA (16S rDNA) of 18 firefly species from Southwest of china. Combined with homologous sequences previously reported, phylogenetic trees including Japanese, Korean and chinese species were reconstructed by neighbor-joining, maximum parsimony and Bayesian methods. All reconstructions agree on most nodes of the trees. Monophyly of Lampyridae is not supported because Rhagophthalmus ohbai in Rhagophthalmidae is included within it. Lamprigera, a genus placed unreliably in Lampyrinae, shows a close relationship to Amydetinae. Monophyly of Luciolinae is not supported because Pristolycus sagulatus (Lampyrinae) is included within it. In the Luciolinae, monophyly of Curtos and Hotaria is well established, respectively, but both morphological and molecular data continue to indicate that Luciola is not monophyletic and its subdivision is indeed necessary. Within the Lampyrinae, both Pyrocoelia and Diaphanes are not monophyletic, but monophyly of Pyrocoelia + Diaphanes is well supported. Phylogeny of Diaphanes is discussed for the first time. Generic placement of a newly discovered species (Diaphanes pectinealis Li et Liang) sharing some characters of Pyrocoelia and Diaphanes challenges the delimitation of these two similar genera. With references to the firefly mating systems, we suggest that more emphases should be placed on those sexually selected characters such as antennal structure in taxonomy of Lampyridae.

关键词： Lampyridae mitochondrial 16S rDNA morphological and ethological traits phylogeny.

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Structural Analysis and Identification of Cis-Elements of Rice osRACD Gene

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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 191-198页

作者： Yun-Zhe XU, Rui-Lin YOU and Nai-Hu WU institute of Genetics and Developmental Biology, chinese academy of sciences, beijing 100080,{3. 2College of Life sciences, Peking University, beijing 100871,{3. institute of Genetics and Developmental Biology Chinese Academy of Sciences College of Life sciences Peking University

The osRACD gene correlated with fertility transformation in the photoperiod sensitive genic male sterile rice (PGMR), Nongken 58S, encoded a rice (Oryza sativa L. ssp. japonica) small GTPase belonging to the Rac/Rho family. Inverse PCR was performed to amplify a fragment about 1.4 kb in 5' upstream region of the osRACD promoter. Deletion mutation and gel mobility shift assay characterized two fragments (–799 to –686 nt, and –686 to –43. nt) in the osRACD promoter that could be involved in its transcriptional regulation. When these two deletion fragments were used as probe respectively, a retarded band appeared in the nuclear extracts of fertile 58S rice under short day (58S-SD). Whereas no retarded band was shown in the nuclear extracts of sterile 58S rice under long day (58S-LD). Competition assay indicated that the factors in the retarded bands binding to these two fragments were the same trans-acting factor (termed rice factor, RF). The binding affinity of RF was affected by phosphorylation and was higher in SD-growth rice than that of LD-growth rice.

关键词： photoperiod-sensitive male genic sterile rice osRACD gene photoperiod fertility transformation cis-element

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Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2,3., LI Xiao-wei 2,3.. School of Information Engineering, Zhejiang Forestry College, Hangzhou 3.13.0, Zhejiang, china 2. institute of Computing Technology, chinese academy of sciences,{3., china 3. Graduate School of the chinese academy of sciences, beijing 10003., china School of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

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Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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Science china Earth sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3. GUO Zhengtang2,1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. institute of Geology and Geophysics, chinese academy of sciences, beijing 100029,{3. 2. institute of Earth Environment, chinese academy of sciences, Xi’an 710075,{3. 3. institute of Geomechanics, chinese academy of Geological sciences, beijing 100081,{3. 1. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China 2. institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 253.1 m sequence varies from 6 to 13.μm and the > 63.μm fraction representsonly 5.3. in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

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Studies on the Condensed Structure of Vacuum Cast Atactic Polystyrene Films

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Chemical Research in chinese Universities 2000年第4期16卷 363-368页

作者： WANG You, HE Chu-ning and SHEN Jing-shu (Polymer Physics laboratory, institute of Chemistry, chinese academy of sciences,{3., china) WU Li-heng and SONG Qing (china Textile academy, beijing 100025, china) chinese Acad Sci Inst Chem Polymer Phys Lab Beijing 100080 Peoples R China china Text Acad Beijing 100025 Peoples R China

The condensed structure of atactic-polystyrene (a - PS ) films cast from the solutions of differ- ent concentrations in dichloromethane under vacuum and atmospheric conditions was studied by differential scanning calorimetry(DSC). It was found that only under vacuum evaporating conditions did the endothermic peak in the DSC curves of a-PS films depend on the concentration of the a-PS solution. For the samples cast from the solution of concentration below 0. 010 g/mL, no endothermal peak was observed, but for those cast from the solution of concentration above 0. 020 g/mL, obvious endothermal peaks appeared. The onset of the endothermal peak is correlated with the critical overlapping concentration c' (0. 010-0. 020 g/mL), which is in agreement with the theoretically calculated one (Ccal=0.014 g/mL).

关键词： Differential scanning calorimeter(DSC) Critical overlapping concentration Atactic polystyrene film

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An improved method for evaluating the seasonal variability of total suspended sediment flux field in the Yellow and East china Seas

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International Journal of Sediment Research 2011年第1期26卷 1-14页

作者： PANG Chongguang~1,YU Wei~2,YANG Yang~3.and HAN Danxiu~4 institute of Oceanology,chinese academy of {3.,Qingdao 266071,china, 2 institute of Oceanology,chinese academy of {3.,Qingdao 266071,china,Graduate School of chinese academy of sciences,beijing 10003.,china 3.institute of Oceanology,chinese academy of {3.,Qingdao 266071,china,Graduate School of chinese academy of sciences,beijing 10003.,china 4 china University of Petroleum,beijing 102249,china [a] Doctor Researcher institute of Oceanology chinese academy of sciences Qingdao 266071 china [b] institute of Oceanology chinese academy of sciences Qingdao 266071 china Graduate School of chinese academy of sciences beijing 10003. china [c] institute of Oceanology chinese academy of sciences Qingdao 266071 china Graduate School of chinese academy of sciences beijing 10003. china [d] china University of Petroleum beijing 102249 china

The suspended sediment flux field in the Yellow and East china Seas(YECS) displays its seasonal variability.A new method is introduced in this paper to obtain the flux field via retrieval of ocean color remote sensing data,statistical analysis of historical suspended sediment concentration data,and numerical simulation of three-dimensional(3.) flow *** components of the sediment flux field include(i) surface suspended sediment concentration inverted from ocean color remote sensing data;(ii) vertical distribution of suspended sediment concentration obtained by statistical analysis of historical observation data;and(iii) 3. flow field modeled by a numerical *** the improved method,the 3. suspended sediment flux field in the YECS has been *** comparison with the suspended sediment flux field solely based on the numerical simulation of a suspended sediment transport model,the suspended sediment flux field obtained by the improved method is found to be more *** 3. suspended sediment flux field from ocean colour remote sensing and in situ observation are more closer to the ***,by quantitatively analyzing the newly obtained suspended sediment flux field,the quantity of sediment erosion and deposition within the different regions can be *** sediment exchange between the Yellow Sea and the East china Sea can be *** mechanism of suspended sediment transport in the YECS can be better *** particular,it is suggested that the long-term transport of suspended sediment is controlled mainly by the circulation pattern,especially the current in winter.

关键词： Suspended sediment flux field Seasonal variability Yellow and East china Seas Regression equation Numerical simulation

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Comparisons of Limit Analysis Solutions and Random Search Solutions on Slope Critical Slip Surface

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Communications in Nonlinear Science and Numerical Simulation 1998年第2期3卷 14-19页

作者： Jianfeng WANG (LNM, institute of mechanics, CAS, beijing 100080, china) LNM Institute of Mechanics CAS Beijing 100080 China

ＩｎｔｒｏｄｕｃｔｉｏｎＤｅｓｐｉｔｅｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｅｌａｓｔｉｃｐｌａｓｔｉｃｖｉｓｃｏｕｓｎｕｍｅｒｉｃａｌｍｅｔｈｏｄｓｆｏｒｔｈｅａｎａｌｙｓｉｓｏｆｓｌｏｐｅｓ，ｔｒａｄｉｔｉｏｎａｌ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＤｅｓｐｉｔｅｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｅｌａｓｔｉｃｐｌａｓｔｉｃｖｉｓｃｏｕｓｎｕｍｅｒｉｃａｌｍｅｔｈｏｄｓｆｏｒｔｈｅａｎａｌｙｓｉｓｏｆｓｌｏｐｅｓ，ｔｒａｄｉｔｉｏｎａｌｔｅｃｈｎｉｑｕｅｓｂａｓｅｄｏｎ...

关键词： limit state analysis upper bound theorem random searching slip surface slope stability plasticity

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