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Leachate Lithium Characteristics of Loess-paleosol Sequences on the Chinese Loess Plateau and their Paleoclimatic Significance
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作者 JIA Peng FU Chaofeng +4 位作者 HE Maoyong LIU Junfeng LIU Na LI Yulong YANG Kaiyuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1814-1824,共11页
The geochemical components of the leachate from loess-paleosol deposits can provide information about climaterelated post-depositional processes.For example,leachate lithium([Li]_(leachate))is a potential paleoclimate... The geochemical components of the leachate from loess-paleosol deposits can provide information about climaterelated post-depositional processes.For example,leachate lithium([Li]_(leachate))is a potential paleoclimate proxy because lithium is a typical lithophile element that is readily adsorbed by clay minerals during weathering and pedogenesis,and thus stratigraphic variations in[Li]leachatecan reflect these processes.We investigated the[Li]leachatevalues of two loess-paleosols profiles(the Luochuan and Weinan sections),on a north-south climatic gradient on the Chinese Loess Plateau.Independent paleoclimate information was provided by measurements of magnetic susceptibility,grain size,Rb/Sr ratios,and clay mineral content.During the last glacial-interglacial period,[Li]leachateincreased from 0.39 to 1.97μg/g at Luochuan and from 0.67 to 2.45μg/g at Weinan,mainly due to increasing pedogenesis.Based on these results we developed a conceptual model to explain the variations in[Li]leachate,Li^(+)within loess layers is mainly derived from dust input and the decomposition of primary minerals,influenced by the East Asian winter monsoon,while in paleosol layers Li is mainly derived from clay mineral adsorption during pedogenic processes,influenced by the East Asian summer monsoon. 展开更多
关键词 leachate lithium concentration loess-paleosol sequences last glacial-interglacial cycle paleoclimate record
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A preliminary study of the quantitative couplingbetween loess-paleosol sequences and summermon soon changes 被引量:4
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作者 HAO Yong-ping FANGXiao-min LIJi-jun(LREIS, Institute of Geography, CAS, Beijing 100101 China: Dept. of Geography, LanzhouUniversity, Lanzhou 730000, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第4期394-401,共8页
The Loess Plateau-Northeastern Tibetan Plateau in China is famous for its deep andcontmuous distributed loess, in which soils (developed from loess) vary gradually with differentbiological climates changing from subhu... The Loess Plateau-Northeastern Tibetan Plateau in China is famous for its deep andcontmuous distributed loess, in which soils (developed from loess) vary gradually with differentbiological climates changing from subhumid to arid, which provide a natural proving ground forstUd}’ the coupling of loess-paleosol and climatic changes quantitatively. Thirty-two sections weresampled (collected) for measuring chemical element contents, clay content (and other items) and 60sections were collected for carbonate analysis to establish transfer functions between pedogenesisand climate. Finally, we estimated the paleoclAnate (P/T) in the region with transfer functions,It isrevealed that the variation of paleocldriate reflected by transfer functions accorded closely with theclimatic pattern resulted from recent work. Specifically, it was about 140 ha BP that summermonsoon reached Lanzhou or further, paleosol S1 (equaling to MIS 5 in deep sea records) developedstrongly in a large scale, even touching upon northeanstern Tibetan Plateau. And, the estimated P/Tinformation also indicated the cold and humid period during 50-30 ka BP, mean annual Precipitationwas about 400-500 nun in Angutan recorded by mega-interstadial paleosol Sm. 展开更多
关键词 LOESS Plateau NORTHEASTERN Tibetan PLATEAU pedogedsis loess-paleosol sequences summer MONSOON transfer functions
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Red Ratings for Loess-Paleosol Sequences on China’s Loess Plateau and Their Paleo-Climatic Implications 被引量:5
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作者 HUXue-Feng LUHua-Yu +2 位作者 XUQi DONGLi-Jing HUXing 《Pedosphere》 SCIE CAS CSCD 2004年第4期433-440,共8页
Comparisons of red ratings (RR) with Fed, Fed/Fet, clay content, and magnetic susceptibility (X) of two loess-paleosol sequences at Luochuan and Lingtai on China's Loess Plateau were conducted to study the possibl... Comparisons of red ratings (RR) with Fed, Fed/Fet, clay content, and magnetic susceptibility (X) of two loess-paleosol sequences at Luochuan and Lingtai on China's Loess Plateau were conducted to study the possible relationship between RR and pedogenic degrees of the two loess-paleosol sequences, and to discuss whether the RR could become new paleo-climatic indicators. Results showed that the RR of the two loess-paleosol sequences had positive, highly significant (P < 0.01)correlations with: 1) citrate-bicarbonate-dithionite (CBD) extracted iron (Fed), 2) ratios of CBD extracted iron to total iron (Fed/Fet), 3) clay (< 2 μm), and 4) magnetic susceptibility (X). This suggested that the RR of these loess-paleosol sequences could indicate degrees of loess weathering and pedogenesis and were potential paleo-climatic proxies. The strong correlations of RR to Fed and X also implied that during pedogenic processes, pedogenic hematite in loess and paleosols were closely related to the amount of total secondary iron oxides and pedogenic ferrimagnetic minerals (predominantly maghemite). 展开更多
关键词 赤铁矿 黄土高原 古土壤序列 磁化系数 中国西北地区
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Major elements in the Holocene loess-paleosol sequence in the upper reaches of the Weihe River valley,China 被引量:1
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作者 WAN Honglian HUANG Chunchang PANG Jiangli 《Journal of Arid Land》 SCIE CSCD 2016年第2期197-206,共10页
Palaeohydrological investigations were carried out in the Guchuan Basin in the upper reaches of the Weihe River valley, China. A set of palaeoflood slackwater deposits(SWDs) was found interbedded in the Holocene loess... Palaeohydrological investigations were carried out in the Guchuan Basin in the upper reaches of the Weihe River valley, China. A set of palaeoflood slackwater deposits(SWDs) was found interbedded in the Holocene loess-paleosol sequence at the Guchuanzhen site(GCZ). These palaeoflood SWDs were studied by field observations and laboratory analyses including concentrations of chemical elements and optically stimulated luminescence(OSL) dating. The results showed that the palaeoflood SWDs were the result of the secondary separations of the surface soil and weathered soil layers during the process of water transport and deposition, and without obvious weathering during soil development. These extraordinary flood events were dated back to 3,200-3,000 a B.P. with the OSL method and checked by archaeological dating of the human remains retrieved from the profile. These extraordinary flood events were therefore considered as regional expression of known climatic events and demonstrated the climatic instability in the Holocene. This result is important for understanding the effects of global climate change on the dynamics of river systems. 展开更多
关键词 黄土-古土壤序列 全新世黄土 渭河流域 化学元素 中上游 中国 全球气候变化 洪水事件
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The Application of Nicotiana benthamiana as a Transient Expression Host to Clone the Coding Sequences of Plant Genes
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作者 Jianzhong Huang Peng Jia +3 位作者 Xiaoju Zhong Xiuying Guan Hongbin Zhang Honglei Ruan 《American Journal of Molecular Biology》 CAS 2024年第2期54-65,共12页
Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using co... Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using complementary DNA (cDNA) derived from messenger RNA (mRNA) extracted from plant tissues and generated by reverse transcription. However, some CDS are difficult to acquire through this process as they are expressed at extremely low levels or have specific spatial and/or temporal expression patterns in vivo. These challenges require the development of alternative CDS cloning technologies. In this study, we found that the genomic intron-containing gene coding sequences (gDNA) from Arabidopsis thaliana, Oryza sativa, Brassica napus, and Glycine max can be correctly transcribed and spliced into mRNA in Nicotiana benthamiana. In contrast, gDNAs from Triticum aestivum and Sorghum bicolor did not function correctly. In transient expression experiments, the target DNA sequence is driven by a constitutive promoter. Theoretically, a sufficient amount of mRNA can be extracted from the N. benthamiana leaves, making it conducive to the cloning of CDS target genes. Our data demonstrate that N. benthamiana can be used as an effective host for the cloning CDS of plant genes. 展开更多
关键词 Coding sequence Genomic sequence Nicotiana benthamiana Plant Genes
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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector Watermarking
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作者 Rafi Ullah Mohd Hilmi bin Hasan +1 位作者 Sultan Daud Khan Mussadiq Abdul Rahim 《Computers, Materials & Continua》 SCIE EI 2024年第3期3283-3301,共19页
Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all whil... Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image quality.Moreover,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy protocols.Nevertheless,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression alone.In response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking scheme.The watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion vectors.In the process of watermark embedding,motion vectors are selected based on their magnitude and phase angle.When embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the images.The embedding of watermark bits is dependent on motion vectors.Although reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking method.The reason for this is that the use of reversible watermarks may impede the claims of ownership and legal rights.The restoration of original data or images may call into question ownership or other legal claims.The peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image quality.Across all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds 0.92.Experimental results substantiate the efficacy of the proposed technique in preserving data integrity. 展开更多
关键词 Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence WATERMARKING
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Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface
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作者 Lei Yang Jianjun Wang Caijun Xu 《Geodesy and Geodynamics》 EI CSCD 2024年第1期1-12,共12页
Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6... Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,2021.The spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among them.Here we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction interface.Our results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,respectively.The Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%respectively.Other factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench. 展开更多
关键词 The 2020-2021 Alaska earthquake sequence Coseismic Coulomb stress change Mainshock-aftershock triggering The Alaska-Aleutian subduction interface The Shumagin gap
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Intelligent extraction of road cracks based on vehicle laser point cloud and panoramic sequence images
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作者 Ming Guo Li Zhu +4 位作者 Ming Huang Jie Ji Xian Ren Yaxuan Wei Chutian Gao 《Journal of Road Engineering》 2024年第1期69-79,共11页
In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strat... In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road cracks.This methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of images.The study employs a vehicle-mounted LiDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence image.The extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic image.Additionally,a threshold value is set based on the crack elevation change to extract the aligned roadway point cloud.The three-dimensional data pertaining to the cracks can be acquired.The experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road cracks.The utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road cracks.This approach exhibits superior accuracy when compared to conventional methods.Moreover,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic safety.Consequently,this technique finds extensive application in the domains of intelligent transportation and urbanization development.The technology exhibits significant promise for use in the domains of intelligent transportation and city development. 展开更多
关键词 Road crack extraction Vehicle laser point cloud Panoramic sequence images Convolutional neural network
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Improving the accuracy of genomic prediction for meat quality traits using whole genome sequence data in pigs 被引量:1
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作者 Zhanwei Zhuang Jie Wu +14 位作者 Yibin Qiu Donglin Ruan Rongrong Ding Cineng Xu Shenping Zhou Yuling Zhang Yiyi Liu Fucai Ma Jifei Yang Ying Sun Enqin Zheng Ming Yang Gengyuan Cai Jie Yang Zhenfang Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第5期1880-1894,共15页
Background Pork quality can directly affect customer purchase tendency and meat quality traits have become valu-able in modern pork production.However,genetic improvement has been slow due to high phenotyping costs.In... Background Pork quality can directly affect customer purchase tendency and meat quality traits have become valu-able in modern pork production.However,genetic improvement has been slow due to high phenotyping costs.In this study,whole genome sequence(WGS)data was used to evaluate the prediction accuracy of genomic best linear unbiased prediction(GBLUP)for meat quality in large-scale crossbred commercial pigs.Results We produced WGS data(18,695,907 SNPs and 2,106,902 INDELs exceed quality control)from 1,469 sequenced Duroc×(Landrace×Yorkshire)pigs and developed a reference panel for meat quality including meat color score,marbling score,L*(lightness),a*(redness),and b*(yellowness)of genomic prediction.The prediction accuracy was defined as the Pearson correlation coefficient between adjusted phenotypes and genomic estimated breeding values in the validation population.Using different marker density panels derived from WGS data,accuracy differed substantially among meat quality traits,varied from 0.08 to 0.47.Results showed that MultiBLUP outperform GBLUP and yielded accuracy increases ranging from 17.39%to 75%.We optimized the marker density and found medium-and high-density marker panels are beneficial for the estimation of heritability for meat quality.Moreover,we conducted genotype imputation from 50K chip to WGS level in the same population and found average concord-ance rate to exceed 95%and r^(2)=0.81.Conclusions Overall,estimation of heritability for meat quality traits can benefit from the use of WGS data.This study showed the superiority of using WGS data to genetically improve pork quality in genomic prediction. 展开更多
关键词 Genomic prediction Meat quality PIGS Whole genome sequence
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A Novel Method of Deinterleaving Radar Pulse Sequences Based on a Modified DBSCAN Algorithm 被引量:1
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作者 Abolfazl Dadgarnia Mohammad Taghi Sadeghi 《China Communications》 SCIE CSCD 2023年第2期198-215,共18页
A modified DBSCAN algorithm is presented for deinterleaving of radar pulses in modern EW environments.A main characteristic of the proposed method is that using only time of arrival of pulses,the method can sort the p... A modified DBSCAN algorithm is presented for deinterleaving of radar pulses in modern EW environments.A main characteristic of the proposed method is that using only time of arrival of pulses,the method can sort the pulses efficiently.Other PDW information such as rise time,carrier frequency,pulse width,modulation on pulse,fall time and direction of arrival are not required.To identify the valid PRIs in a set of interleaved pulses,an innovative modification of the DBSCAN algorithm is introduced which is accurate and easy to implement.The proposed method determines valid PRIs more accurately and neglects the spurious ones more efficiently as compared to the classical histogram based algorithms such as SDIF.Furthermore,without specifying any input parameter,the proposed method can deinterleave radar pulses while up to 30%jitter is present in the associated PRI.The accuracy and efficiency of the proposed method are verified by computer simulations and real data results.Experimental simulations are based on different real and operational scenarios where the presence of missing and spurious pulses are also considered.So,the simulation results can be of practical significance. 展开更多
关键词 DEINTERLEAVING radar pulse sequences density based clustering pulse descriptor word
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THE CARBONATE ISOTOPIC COMPOSITION OF THE LOESS-PALEOSOL SEQUENCE AND ITS IMPLICATION OF PALEOCLIMATIC CHANGE 被引量:12
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作者 顾兆炎 《Chinese Science Bulletin》 SCIE EI CAS 1991年第23期1979-1983,共5页
The isotopic composition of soil or paleosol carbonate can be a sensitive paleoclimatic indicator. The relationships between the oxygen isotopic composition of modem soil carbonates and that of meteoric waters and bet... The isotopic composition of soil or paleosol carbonate can be a sensitive paleoclimatic indicator. The relationships between the oxygen isotopic composition of modem soil carbonates and that of meteoric waters and between the carbon isotopic composition of the soil carbonates and the fraction of the plants using the C<sub>4</sub> photosynthetic pathway in 展开更多
关键词 Ioess-paleosol sequence CARBONATE ISOTOPIC composition PALEOCLIMATIC change
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Paleo-environmental study on the growth of magnetotactic bacteria and precipitation of magnetosomes in Chinese loess-paleosol sequences 被引量:2
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作者 PENG Xianzhi JIA Rongfen +2 位作者 LI Rongsen DAI Shunying LIU Tungsheng 《Chinese Science Bulletin》 SCIE EI CAS 2000年第S1期21-25,共5页
405 samples were collected from L5-S5-L6 in consideration of obvious variations in susceptibility of the geological sections, which are section Xifeng in Gansu Province and section Duanjiapo in Shaanxi Province for st... 405 samples were collected from L5-S5-L6 in consideration of obvious variations in susceptibility of the geological sections, which are section Xifeng in Gansu Province and section Duanjiapo in Shaanxi Province for study of magnetotactic bacteria (MB) and magnetosomes (MS) in Chinese loess-paleosol sequences. MB in each sample were observed by TEM after being cultured under 8-18℃, room temperature (RT), 25℃, 26℃ and 30℃ conditions. In general, MB are distributed widely in loess-paleosol sequences, fewer in loess layers with predomination of vibriod in shape. However, there are more MB in paleosol layers with morphological varieties such as roddish, vibriod and occasionally approximately coccus. The magnetosomes (MS) in MB of paleosol are usually arranged in chains along the cells. It was also found that MB growth and MS formation are associated with the environment in which MB live. It can be inferred from the distributions of MB and MS that the paleoclimates fluctuated during the formation of 展开更多
关键词 loess-paleosol sequenceS magnetotactic BACTERIA (MB) MAGNETOSOMES (MS) paleoeclimate SECTION Xifeng SECTION Duanjiapo.
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Loess-paleosol sequence on Loess Plateau and uplift of the Qinghai-Xizang Plateau 被引量:3
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作者 吴锡浩 安芷生 《Science China Earth Sciences》 SCIE EI CAS 1996年第2期121-133,共13页
Correlation of the loess-paleosol sequence on Loess Plateau and the tectonodimatic cycle it reflects with the moraine-paleosol sequence on Qingbai-Xizang Plateau and the uplift process it reflects, indicates that both... Correlation of the loess-paleosol sequence on Loess Plateau and the tectonodimatic cycle it reflects with the moraine-paleosol sequence on Qingbai-Xizang Plateau and the uplift process it reflects, indicates that both sequences are synchronous to each other on phase variation with a quasi-period of 0.4 Ma, i.e. the eccentricity variation period. The response of the variation of the Asian paleomonsoon and the paleoclimatic change to the uplift stages and altitudes and the underlying surfaces is studied. 展开更多
关键词 loess PALEOSOL sequence uplift of QINGHAI-XIZANG Plateau MORAINE PALEOSOL sequence tectonoclimatic cycles paleomonsoon.
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PRI modulation recognition and sequence search under small sample prerequisite 被引量:2
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作者 ZHANG Chunjie LIU Yuchen SI Weijian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期706-713,共8页
Pulse repetition interval(PRI)modulation recognition and pulse sequence search are significant for effective electronic support measures.In modern electromagnetic environments,different types of inter-pulse slide rada... Pulse repetition interval(PRI)modulation recognition and pulse sequence search are significant for effective electronic support measures.In modern electromagnetic environments,different types of inter-pulse slide radars are highly confusing.There are few available training samples in practical situations,which leads to a low recognition accuracy and poor search effect of the pulse sequence.In this paper,an approach based on bi-directional long short-term memory(BiLSTM)networks and the temporal correlation algorithm for PRI modulation recognition and sequence search under the small sample prerequisite is proposed.The simulation results demonstrate that the proposed algorithm can recognize unilinear,bilinear,sawtooth,and sinusoidal PRI modulation types with 91.43% accuracy and complete the pulse sequence search with 30% missing pulses and 50% spurious pulses under the small sample prerequisite. 展开更多
关键词 inter-pulse slide pulse repetition interval(PRI)modulation type bi-directional long short-term memory(BiLSTM)network sequence search
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Complicated expansion trajectories of insertion sequences and potential association with horizontal transfer of Wolbachia DNA
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作者 Yun-Heng Miao Da-Wei Huang Jin-Hua Xiao 《Zoological Research》 SCIE CAS CSCD 2023年第2期273-275,共3页
DEAR EDITOR,Insertion sequences(ISs) are the simplest structural transposable elements(TEs) in prokaryotes, consisting only of a transposase coding sequence and its bilateral short terminal inverted repeats. Due to th... DEAR EDITOR,Insertion sequences(ISs) are the simplest structural transposable elements(TEs) in prokaryotes, consisting only of a transposase coding sequence and its bilateral short terminal inverted repeats. Due to their gradually streamlined genomic construction, TEs rarely exist in the genomes of obligate endosymbionts. However, TE content, especially ISs. 展开更多
关键词 sequenceS INSERTION WOLBACHIA
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Modeling and simulation of dynamic carbonate deposition in a loess-paleosol sequence 被引量:1
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作者 LI Xuyong LI Baoguo +4 位作者 LU Huayi DUAN Jiannan SHI Yuanchun Commission for Integrated Survey of Natural Resources, CAS, Beijing 100101, China Department of Soil and Water, China Agricultural University, Beijing 100094. China Xian Laboratory for Loess and Quaternary Research, CAS, Xian 710054, China, Institude of the Loess Plateau. Shanxi University, Taiyuan 030000, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第S1期211-217,共7页
A compartment model of dynamic deposition processes has been developed and testedin the Potou loess section of China. There are four components in the model : carbonate input ofeolian dust, carbonate output of erosion... A compartment model of dynamic deposition processes has been developed and testedin the Potou loess section of China. There are four components in the model : carbonate input ofeolian dust, carbonate output of erosion, carbonate chemical equilibrium and soil water balance. Aclimate stochastic model software (CLIMAK) generates the daily weather data. The processes ofeolian dust deposition, erosion, and pedogenesis simulate the complex process of carbonatedeposition in a loess-paleosol sequence. We consider both climatic change and soil-forming factors.The results indicate that since the Late Pleistocene in Potou section, the mean carbonate fluxesfrom precipitation, eolian dust and erosion are 0.14g/cm^2/kg, 1.45g/cm^2/ka and 0.23g/cm^2/karespectively. Of this, 91.2% of the carbonate input is from eolian dust. 展开更多
关键词 CARBONATE COMPARTMENT model loess-paleosol EOLIAN DUST EROSION
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Identification of clade-wide putative cis-regulatory elements from conserved non-coding sequences in Cucurbitaceae genomes
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作者 Hongtao Song Qi Wang +2 位作者 Zhonghua Zhang Kui Lin Erli Pang 《Horticulture Research》 SCIE CSCD 2023年第4期238-248,共11页
Cis-regulatory elements regulate gene expression and play an essential role in the development and physiology of organisms.Many conserved non-coding sequences(CNSs)function as cis-regulatory elements.They control the ... Cis-regulatory elements regulate gene expression and play an essential role in the development and physiology of organisms.Many conserved non-coding sequences(CNSs)function as cis-regulatory elements.They control the development of various lineages.How-ever,predicting clade-wide cis-regulatory elements across several closely related species remains challenging.Based on the relationship between CNSs and cis-regulatory elements,we present a computational approach that predicts the clade-wide putative cis-regulatory elements in 12 Cucurbitaceae genomes.Using 12-way whole-genome alignment,we first obtained 632112 CNSs in Cucurbitaceae.Next,we identified 16552 Cucurbitaceae-wide cis-regulatory elements based on collinearity among all 12 Cucurbitaceae plants.Furthermore,we predicted 3271 potential regulatory pairs in the cucumber genome,of which 98 were verified using integrative RNA sequencing and ChIP sequencing datasets from samples collected during various fruit development stages.The CNSs,Cucurbitaceae-wide cis-regulatory elements,and their target genes are accessible at http://cmb.bnu.edu.cn/cisRCNEs_cucurbit/.These elements are valuable resources for functionally annotating CNSs and their regulatory roles in Cucurbitaceae genomes. 展开更多
关键词 elements CONSERVED sequenceS
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Sedimentary architecture and distribution of intra-platform shoal in sequence framework of Permian Changxing Formation in central Sichuan Basin,SW China
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作者 WANG Dong LIU Hong +7 位作者 TANG Song BAI Jinhao ZHOU Gang LI Zhengyong LIANG Feng TAN Xiucheng GENG Chao YANG Ying 《Petroleum Exploration and Development》 SCIE 2023年第2期388-403,共16页
Based on the comprehensive analysis of core, thin section, logging and seismic data, this study carried out the identification and comparison of Permian Changxing Formation sequences, clarified the typical sedimentary... Based on the comprehensive analysis of core, thin section, logging and seismic data, this study carried out the identification and comparison of Permian Changxing Formation sequences, clarified the typical sedimentary architectures of intra-platform shoal, investigated the vertical and horizontal development and distribution of intra-platform shoal in each sequence, and thus established the sedimentary evolution model of shoal body. The study results are reflected in four aspects.First, there are two complete third-order sequences(SQ1 and SQ2) in Changxing Formation in central Sichuan Basin. SQ1 is generally thick in the north and thin in the south, and SQ2 shows a thickness differentiation trend of “two thicknesses and three thinnesses”. Second, the Changxing Formation in central Sichuan Basin mainly develops intra-platform shoal, inter-shoal sea and intra-platform depression subfacies. In the vertical direction, the intra-platform shoal mainly presents two typical sedimentary sequences: stable superposed and high-frequency interbedded. Third, the stable superimposed sedimentary sequence is developed in the shoal belt at the edge of intra-platform depression, which is composed of two shoal-forming periods and located in the highstand systems tracts(HSTs) of SQ1 and SQ2. The high-frequency interbedded sedimentary sequence is developed in the southern shoal belt of intra-platform depression, which is composed of four shoal-forming periods and mainly located in the HST of SQ2. Fourth, during the SQ1 deposition, the intra-platform shoal was mainly developed at the edge of the intra-platform depression on the north side of the study area, and the inter-shoal sea subfacies was mainly developed on the south side. During the SQ2 deposition, the intra-platform shoal was widely developed in the area, forming two nearly parallel intra-platform shoal belts. The study results provide direction and ideas for exploration of Changxing Formation intra-platform shoal reservoirs in central Sichuan Basin. 展开更多
关键词 Sichuan Basin Permian Changxing Formation intra-platform shoal sequence stratigraphic framework typical sedimentary sequence sedimentary evolution model
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Biostratigraphy,Microfacies,Sedimentary Environments and Sequence Stratigraphy of the Late Devonian-Carboniferous Deposits at the Anarak Section,Central Iran
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作者 Elaheh SATTARI Ali BAHRAMI +2 位作者 Hossein VAZIRI-MOGHADDAM Azizollah TAHERI Iliana BONCHEVA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1038-1057,共20页
The Late Devonian-early Carboniferous deposits of the Anarak section in northeastern Isfahan,Central Iran,evaluated based on conodont biostratigraphy,sedimentary environment and sequence stratigraphy.According to the ... The Late Devonian-early Carboniferous deposits of the Anarak section in northeastern Isfahan,Central Iran,evaluated based on conodont biostratigraphy,sedimentary environment and sequence stratigraphy.According to the field observations,five lithological units were identified.Investigating the conodont fauna of the Late Devonian-Carboniferous(Mississippian-Pennsylvanian)deposits of Bahram,Shishtu,and Qaleh(Sardar 1)formations in Anarak section led to the identification of 67 species of 18 conodont genera,and accordingly 22 conodont biozones were differentiated.The correlation of sea-level change curves,regarding to the conodont biofacies with the global sea-level curve,demonstrates the relative correlation in the mentioned times due to the shallow condition of the central Iran basin compared to the European and American basins.The microfacies analysis led to the identification of 12 microfacies related to the open sea,bioclastic barrier,lagoon and tidal flat sub-sedimentary environments in a homoclinal carbonate ramp environment.Based on sequence stratigraphy studies,three 3rd order sequences were identified.The first sequence,which is of the Late Devonian(upper part of the Bahram Formation,32.5 m),the second sequence(12.5 m)is the Late Devonian(uppermost part of the Bahram Formation),and the third sequence(68 m)is the early Carboniferous(the Shishtu I Formation). 展开更多
关键词 sequence stratigraphy CONODONT DEVONIAN CARBONIFEROUS Anarak central Iran
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Competing Patterns in Bernoulli Sequence of Trials
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作者 Paul Vrbik Jan Vrbik 《Applied Mathematics》 2023年第5期314-323,共10页
Consider performing a sequence of Bernoulli trials (each resulting in either a success, denoted S, or a failure F, with a probability of p and q := 1 - p respectively) until one of m specific strings (or patterns) of ... Consider performing a sequence of Bernoulli trials (each resulting in either a success, denoted S, or a failure F, with a probability of p and q := 1 - p respectively) until one of m specific strings (or patterns) of consecutive outcomes is generated. This can be seen as a game where m players select one such pattern each and the one whose pattern occurs first wins. We present symbolic formulas for the m probabilities of winning, and for the mean number of trials and the corresponding standard deviation to complete this game. Several numerical examples are presented, including a search for optimal strategy. 展开更多
关键词 Competing Patterns Bernoulli sequence of Trials Game Theory
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