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Statistical analyses of metric data of hominoid teeth found in Yuanmou of china

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chinese Science Bulletin 2000年第10期45卷 936-942页

作者： LIU Wu, ZHENG Liang & JIANG Chu1. institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, Beijing 100044,{2. 2. institute of Archaeology of Yunnan Province, Kunming 650118,{2. 3. Yuanmou Man Museum, Yuanmou 6513.0,{2. institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China institute of Archaeology of Yunnan Province Kunming China Yuanmou Man Museum Yuanmou China

Mesial-distal and buccal-lingual dimensions of 1 2.6 hominoid teeth found in Yuanmou of Yunnan Province during the period of 1986 and 1988 have been measured. The statistical analyses of the metric data show that the tooth sizes of Yuanmou hominoid can be divided into big and small two types, and most tooth dimensions display obvious bimodalities in both histograms and 2.dimensional plots. The coefficients of variance (CV) reveal that the CVs of Yuanmou hominoid tooth sizes are within or close to the CV ranges of Lufengpithecus and extant great apes. The comparisons of tooth sizes and their proportions indicate that Yuanmou hominoids have close affinities with Lefeng and Kaiyuan hominoids, and have obvious differences with Gorilla, Chimpanzee and Orangutan. The authors believe that the hominoid fossils found in Yuanmou in the past 10 years represent a single species with highly sexual dimorphism in morphology and this species may have a close evolutionary relationship with the hominoids found in

关键词： human origin Yuanmou hominoid dental metrics statistical analyses.

A note on noncommutative moment problems

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Science china Mathematics 2005年第8期48卷 1144-1151页

作者： MA Xiujuan School of sciences, Hebei University of Technology, Tianjin 3.013., china Mathematics institute, {3. of Mathematics and Systems Science, chinese academy of sciences, Beijing 100080, china 1. School of sciences Hebei University of Technology 300130 Tianjin China 2. Mathematics institute Academy of Mathematics and Systems Science Chinese Academy of Sciences 100080 Beijing China

Noncommutative moment problems for C*-algebras are studied. We generalize a result of Hadwin on tracial states to nontracial case. Our results are applied to obtain simple solutions to moment problems on the square and the circle as well as extend the positive unital functionals from a (discrete) complex group algebra to states on the group C*-algebra.

关键词： moment, free product, state, group C*-algebra.

A two-round honest-verifier zero-knowledge protocol

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Science china(Information sciences) 2010年第5期53卷 954-963页

作者： LIU HanWu 1,2.& LIN DongDai 1 1 The State Key Laboratory of Information Security, institute of software,{2., Beijing 100190,{3. 2.Graduate University of the{2., Beijing 100049,{3. 1. The State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Since the concept of zero-knowledge protocols was introduced, it has attracted a lot of attention and in turn showed significant effect on the development of cryptography, complexity theory and other areas. The round complexity of a zero-knowledge protocol is a very important efficiency consideration, and it is required to be as small as possible. Generally, it is desirable to have zero-knowledge protocols with constant numbers of rounds. Goldreich and Oren proved that only languages in BPP have one-round and two-round zero-knowledge protocols. Moreover, they also showed that only languages in BPP have one-round honest-verifier zero-knowledge protocols. The notion of honest-verifier zero-knowledge protocols is highly non-trivial and fascinating itself, and has many other uses. Thus, the problem as to whether there exist two-round honest-verifier zero-knowledge protocols becomes an important open problem. In this paper, we introduce a new simulation technique and present a two-round honest-verifier zero-knowledge protocol for any language in N P under a standard complexity assumption based on this technique.

关键词： proof system argument system zero-knowledge witness indistinguishability black-box one-way permutation commitment scheme zap

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 {2.,{3. 2.ollege 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

Nitrogen isotopic geochemical characteristics of crude oils in several basins of china

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Science china Earth sciences 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1,2. MEI Bowen1 & CAO Yacheng3.1. Jianghan Petroleum University, Jingzhou 43.100,{2. 2. Huazhong University of Science and Technology, Wuhan 43.047,{2. 3. Nanjing institute of Soil Science,{3., Nanjing 2.0008,{2. 1. Jianghan Petroleum University 434100 Jingzhou China 2. Huazhong University of Science and Technology 430047 Wuhan China 3. Nanjing institute of Soil Science Chinese Academy of Sciences 210008 Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of china have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 15N is in the range of ?6‰-2.‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 15N with the value of about 1‰-5‰ whereas the oils in saline or semi-saline environment have higher δ 15N, with most samples being above 10‰ and some exceeding 17‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 15N below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 15N distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, china.

Validating global hydrological models by ground and space gravimetry

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chinese Science Bulletin 2009年第9期54卷 1534-1542页

作者： ZHOU JiangCun1,2.3. SUN HePing1,2.& XU JianQiao1,2.1 institute of Geodesy and Geophysics,{2., Wuhan 43.077, china 2.Key Laboratory of dynamic geodesy,{2., Wuhan 43.077, china 3.Graduate University of{2., Beijing 100049, china institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of dynamic geodesy Chinese Academy of Sciences Wuhan 430077 China Graduate University of chinese academy of sciences Beijing 100049 China

The long-term continuous gravity observations obtained by the superconducting gravimeters (SG) at seven globally-distributed stations are comprehensively analyzed. After removing the signals related to the Earth's tides and variations in the Earth's rotation, the gravity residuals are used to describe the seasonal fluctuations in gravity field. Meanwhile, the gravity changes due to the air pressure loading are theoretically modeled from the measurements of the local air pressure, and those due to land water and nontidal ocean loading are also calculated according to the corresponding numerical models. The numerical results show that the gravity changes due to both the air pressure and land water loading are as large as 100×10-9 m s-2.in magnitude, and about 10×10-9 m s-2.for those due to the nontidal ocean loading in the coastal area. On the other hand, the monthly-averaged gravity variations over the area surrounding the stations are derived from the spherical harmonic coefficients of the GRACE-recovered gravity fields, by using Gaussian smoothing technique in which the radius is set to be 600 km. Com-pared the land water induced gravity variations, the SG observations after removal of tides, polar mo-tion effects, air pressure and nontidal ocean loading effects and the GRACE-derived gravity variations with each other, it is inferred that both the ground- and space-based gravity observations can effec-tively detect the seasonal gravity variations with a magnitude of 100×10-9 m s-2.induced by the land water loading. This implies that high precision gravimetry is an effective technique to validate the re-liabilities of the hydrological models.

关键词：重力测量水文模型模型验证和空间地面重力变化季节性波动空气压力

The formation and stability of Si_(1-x)C_x alloys in Si implanted with carbon ions

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chinese Science Bulletin 2001年第3期46卷 200-204页

作者： WANG Yinshu, LI Jinmin, JIN Yunfan, WANG Yutian, SUN Guosheng & LIN Lanying1. Department of Physics, Beijing Normal University, Beijing 100875, china 2. institute of Semiconductors,{2., Beijing 100083. china 3. institute of Modern Physics,{2., Lanzhou 73.000, china Department of Physics Beijing Normal University Beijing China institute of Semiconductors Chinese Academy of Sciences Beijing China institute of Modern Physics Chinese Academy of Sciences Lanzhou China

Si1-xCx alloys of carbon (C) concentration between 0.6%-1.0% were grown in Si by ion implantation and high temperature annealing. The formation of Si1-xCx alloys under different ion doses and their stability during annealing were studied. If the implanted dose was less than that for amorphizing Si crystals, the implanted C atoms would like to combine with defects produced during implantation and it was difficult to form Si1-xCx alloys after being annealed at 850℃. With the increment of implanted C ion doses, the lattice damage increased and it was easier to form Si1-xCx alloys. But the lattice strain would become saturate and only part of implanted carbon atoms would occupy the substitutional positions to form Si1-xCx alloys as the implanted carbon dose increased to a certain degree. Once Si1-xCx alloys were formed, they were stable at 950℃, but part of their strain would release as the annealing temperature increased to 1 000℃. Stability of the alloys became worse with the increment of carbon

关键词： ion implantation Si1-xCx alloys stability of Si1-xCx alloys.

Experimental study of composite medium with simultaneously negative permeability and permittivity

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Science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 64-78页

作者： SUI Qiang1, 2.& LI Fang1 1. institute of Electronics, chinese academy of sciences, Beijing {2.,{3. 2. School of Information, Beijing Broadcasting institute, Beijing 10002.,{3. Correspondence should be addressed to Sui Qiang (email: suiqiang@***) Received July 2., 2.03 1. institute of Electronics Chinese Academy of Sciences 100080 Beijing China 2. School of Information Beijing Broadcasting Institute 100024 Beijing China

This paper focuses on a composite medium structure that exhibits simultan- eously negative values of effective permeability and permittivity, and our experimental study in an anechoic chamber. The experiment results show that the artificial medium, based on a periodic array of interspaced conducting nonmagnetic split ring resonators and continuous metallic wires, can have a simultaneously negative effective permeability and permittivity within a frequency region in the microwave regime under certain linearly polarized waves.

关键词： permittivity, permeability, negative index of refraction, split ring resonator, LHM, RHM.

MATRIX ANALYSIS ON LEADING TERM OF CONDITION NUMBER FOR ADDITIVE SCHWARZ METHODS

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Journal of Computational Mathematics 2001年第2期19卷 157-166页

作者： Jia-chang Sun (R & D Center of Paraller software, Laboratory for Computer Science, institute of software,{3.) 中科院软件所

It is well known the order of preconditioned matrix by using additive Schwarz methods. In order to estimate the resulted PCG iteration counts, the related leading term brfore the order is given in this paper.

关键词： additive Schwarz method PCG matrix analysis