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Effects of Predation by Invasive Western Mosquitofish(Gambusia affinis) on Survival of Eggs,Embryos and Tadpoles of Pelophylax nigromaculatus and duttaphrynus melanostictus in South China

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Asian Herpetological research 2016年第1期7卷 46-52页

作者： Xiaoli FAN Zhihua LIN Xiang LI Li WEI Guohua dING College of Ecology Lishui University

Alien species are one of the most serious threats to the decline and extinction of native amphibian populations. In this study, we examined the predation of invasive Western Mosquitofish Gambusia affinis on the eggs, embryos, and tadpoles of duttaphrynus melanostictus and Pelophylax nigromaculatus in south China. Our results suggested that the survival of eggs and embryos remaining in the egg capsules of P. nigromaculatus and d. melanostictus was significantly higher than those removed from the egg capsule at 12-h intervals within 72 h in the presence of G. affinis. The survival of P. nigromaculatus eggs and embryos without egg capsules was significantly lower than those of d. melanostictus without egg capsules. The survival of P. nigromaculatus eggs and embryos with egg capsules was significantly higher than those of d. melanostictus with egg capsules from 24 h to 72 h except for 12 h. The survival of d. melanostictus tadpoles was significantly higher than that of P. nigromaculatus tadpoles in the presence of G. affinis. The survival of Gosner stage 26 tadpoles of P. nigromaculatus was significantly higher than that of Gosner stage 30 tadpoles from 12 h to 60 h, but there were no significant differences at 72 h. In contrast, the survival of Gosner stage 26 tadpoles of d. melanostictus was significantly lower than that of Gosner stage 30 tadpoles within 72 h, recording every 12 h. The increasing temperature caused a significant increase in predation by G. affinis on P. nigromaculatus eggs and embryos. The outer jelly capsule surrounding anurans eggs might serve as a mechanical defense against predation by G. affinis due to its large diameter, relatively stationary state and unpalatability. The differences in the vulnerability of P. nigromaculatus and d. melanostictus embryos and tadpoles to G. affinis probably due to differences in the unpalatability, black skin and activity. Based on the magnitude of predation by G. affinis on the eggs, embryos and tadpoles of thes

关键词： amphibian anura tadpoles eggs embryos predation risk

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SAMPLE-SIZE dETERMINATION FOR TWO INdEPENdENT BINOMIAL EXPERIMENTS

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Journal of Systems Science & Complexity 2011年第5期24卷 981-990页

作者： Zhanping ZHAO NianshengTANG Yunxian LI department of Statistics Yunnan University Kunming 650091 China

Sample size determination is commonly encountered in modern medical studies for two inde- pendent binomial experiments. A new approach for calculating sample size is developed by combining Bayesian and frequentist idea when a hypothesis test between two binomial proportions is conducted. Sample size is calculated according to Bayesian posterior decision function and power of the most powerful test under 0-1 loss function. Sample sizes are investigated for two cases that two proportions are equal to some fixed value or a random value. A simulation study and a real example are used to illustrate the proposed methodologies.

关键词： Bayes factor Bayes posterior decision function binomial proportions power of the mostpowerful test sample-size determination.

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QR factorization for row or column symmetric matrix

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Science China Mathematics 2003年第1期46卷 83-90页

作者：邹红星戴琼海李衍达王殿军 department of Automation Tsinghua University department of Mathematical Sciences Tsinghua University

The problem of fast computing the QR factorization of row or column symmetric matrix isconsidered. We address two new algorithms based on a correspondence of Q and R matrices between the rowor column symmetric matrix and its mother matrix. Theoretical analysis and numerical evidence show that, fora class of row or column symmetric matrices, the QR factorization using the mother matrix rather than therow or column symmetric matrix per se can save dramatically the CPU time and memory without loss of anynumerical precision.

关键词： QR factorization, row or column symmetric matrix, fast computation.

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Study on correlations of modal frequencies and environmental factors for a suspension bridge based on improved neural networks

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Science China(Technological Sciences) 2010年第9期53卷 2501-2509页

作者： dING YouLiang,dENG Yang & LI AiQun Key Laboratory of Concrete and Prestressed Concrete Structure of Ministry of Education,Southeast university,Nanjing 210096,China 1. Key Laboratory of Concrete and Prestressed Concrete Structure of Ministry of Education Southeast University Nanjing 210096 China

By using of long-term monitoring data of Runyang Suspension Bridge,the improved back-propagation neural networks (BPNNs) are formulated for modeling the correlations between modal frequencies and environmental conditions including wind,temperature and vehicle ***,with the correlation models the environmental effects on modal frequencies are quantified and the abnormal changes of measured frequencies are detected by means of the hypothesis *** results reveal that BPNN-based correlation models improved by both early stopping and Bayesian regularization techniques exhibit excellent generalization *** the developed correlation models can effectively reduce the environmental variability in modal *** t-test method provides a good capability to detect the damage-induced 0.16% and 0.12% abnormal changes of the 5th and 6th modal frequencies,***,the proposed method is suitable for real-time monitoring of suspension bridge conditions.

关键词： modal frequency environmental condition correlation artificial neural networks hypothesis test suspension bridge

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philanthropic Activities of Jinan Trade Association in Republic of China

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学术界 2014年第1期 286-292页

作者： Ma dekun College of Politics and International Relations Shandong Normal university

It is one of the significant social functions for the trade associations to actively participate in the social philanthropic *** Trade Associations participated in the social philanthropic activities actively,directly,indirectly,positively and in other ways as *** activities were characterized by being phased,deficiency in initiative and reluctance and so on.

关键词：贸易协会国籍中华社会公益活动社会职能行业协会

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Effect of cooling rate on MC carbide in directionally solidified nickel-based superalloy under high thermal gradient

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China Foundry 2012年第1期9卷 11-14页

作者： Zhang Weiguo Liu Lin Fu Hengzhi College of Mechanical&Electronic Engineering Northwest A&F UniversityYangling 712100China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

A series of directional solidification experiments have been performed to study the effect of cooling rate on the precipitation behavior of MC carbide in nickel-based superalloy under the temperature gradient of 500 K-s^-1. Results reveal that the morphology of MC carbide changes from coarse block to fine strip, then to Chinese-script, and their sizes reduce gradually with the increasing of cooling rate from 2.53 K.s^-1 to 36.4 K.s^-1. At low cooling rates, most of these carbides are found to be located at the grain boundary and interdendritic regions, while the coupled growth of some carbides and 7 matrix in the center of 7 grains is occurred at high cooling rate. The main elements forming MC carbide are Ta, W, and Hf.

关键词： directional solidification cooling rate nickel-based superalloy MC carbide

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Characterization of microbe cementitious materials

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Chinese Science Bulletin 2012年第11期57卷 1333-1338页

作者： RONG Hui QIAN ChunXiang School of Materials Science and Engineering Southeast UniversityNanjing 211189China Jiangsu Key Laboratory of Construction Material Nanjing 211189China

A new generation of cement, microbe cement, has been developed in response to the ever increasing awareness of environmental protection. Microbe cement is a new strengthening material based on microbiologically induced precipitation of calcium carbonate. This paper confirms the feasibility of binding loose sand particles using microbe cement and details the cementation mechanism of microbe cement. We have also prepared microbe cementitious materials (biosandstones). The compressive strength of the bio-sandstone, which depends on the content of calcium carbonate produced by microbially induced precipitation and the bio-mediated calcite crystal size, could be up to 12 MPa at an age of 20 days. By increasing the precipitated calcite content, the compressive strength and microstructure of bio-sandstone could be improved.

关键词：胶凝材料微生物碳酸钙含量方解石晶体生物水泥表征抗压强度环保意识

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Throughput maximization in UWB-based ad-hoc networks

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Science China(Information Sciences) 2010年第12期53卷 2538-2547页

作者： HAAS Zygmunt J. School of Electrical and Computer Engineering Cornell University

In this paper,we study the problem of radio resource allocation,both transmission rates and transmission powers,so as to maximize the throughput of UWB wireless ad-hoc *** analysis is based on the packet-success function(PSF),which is defined as the probability of a data packet being successfully received as a function of the receiver’s signal-to-interference-and-noise-ratio(SINR).We find an optimal link transmission rate,which maximizes the link’s throughput and is dependent on the all active links transmission *** each link transmission rate is adapted to this optimal link transmission rate,then,with single-link operation(i.e.,no other interference sources are present),the link’s throughput is directly proportional to the transmitter’s power and increases indefinitely with increasing transmission ***,with multiplelinks operation and interference each other,as each link transmitting power increases,so does the interference level,and the total network throughput approaches a constant other than ***,for sufficiently small transmission power,the total network throughput of the multiple-links case exceeds the throughput of the single-link case,but the reverse happens for high *** addition,this paper reveals that,as the number of concurrently transmitting links increases,regardless of the power level,the maximal total network throughput approaches a constant,with each link’s throughput approaching *** maximize the network throughput,for the case of small maximal transmission power with weak interference levels,the optimal transmission scheduling allocates simultaneous transmissions of multiple links,but for the case of large maximal transmission power with strong interference levels,the optimal policy assigns separate time for transmission on each *** breakpoint of when to use one link or multiple links is termed the critical *** an example of the analytical calculation of the critical link’s power,we present here so

关键词： UWB impulse radio ad-hoc networks throughput rate power resource allocation

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Solidification microstructure of directionally solidified superalloy under high temperature gradient

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Rare Metals 2012年第6期31卷 541-546页

作者： Zhang Weiguo Liu Lin NW A&F Univ Coll Mech & Elect Engn Yangling 712100 Peoples R China NW Polytech Univ State Key Lab Solidificat Proc Xian 710072 Peoples R China

The effect of solidification rate on the microstructure development of nickel-based superalloy under the temperature gradient of 500 K·cm-1 was studied. The results show that, with the increase of directional solidification rate from 50 to 800 μm·s-1, both the primary and the secondary dendrite arm spacings of the alloy decrease gradually, and the dendrite morphologies transform from coarse dendrite to superfine dendrite. The sizes of all precipitates in the superalloy decrease gradually. The morphology of γ' precipitate changes from cube to sphere shape and distributes uniformly in both dendrite core and interdendritic regions. MC carbide morphology changes from coarse block to fine-strip and then to Chinese-script and mainly consists of Ta, W, and Hf elements. The γ-γ' eutectic fraction increases firstly and then decreases, and similar regularity is also found for the variation of segregation ratio of elements.

关键词： directional solidification superalloy high temperature gradient solidification rate microstructure

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A Robust Noninvasive Approach to Study Gut Microbiota Structure of Amphibian Tadpoles by Feces

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Asian Herpetological research 2018年第1期9卷 1-12页

作者： Xiaowei SONG Jinghan SONG Honghong SONG Qi ZENG Keke SHI College of Life Sciences Xinyang Normal University Institute for Conservation and Utilization of Agro-bioresources in dabie Mountains Xinyang Normal University

The 16S rdNA amplicon high-throughput sequencing technique provides a robust and inexpensive approach to detect the gut microbiota of amphibians. Since different experimental protocols generate technical biases in drawing the gut microbiota profiles, the integrative analysis of gut microbiota produced by different studies must be performed with circumspection. In this study, we compared the efficacy of two dNA extraction methods （i.e., a phenol-chloroform method and TIANamp Stool dNA Kit） in describing intestinal and fecal bacterial communities of transplanted Asiatic toad （Bufo gargarizans） tadpoles. In terms of the dNA extraction quality （i.e., dNA purity and yield rate） and the consistency in between fecal and intestinal microbiota structures （i.e., a and 13 diversity indices）, the phenol-chloroform method was more robust than this commercial stool kit in profiling gut microbiota of tadpoles with feces.

关键词： Bufo gargarizans dNA extraction intestinal microflora phenol-chloroform 16S rdNA

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