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Deep learning on chromatin profiles reveals the cis-regulatory sequence code of the rice genome
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作者 Xinkai Zhou Zhonghao Ruan +2 位作者 Chenlu Zhang Kerstin Kaufmann Dijun Chen 《Journal of Genetics and Genomics》 2025年第6期848-851,共4页
Rice(Oryza sativa)is a staple food for more than half of the world's population and a critical crop for global agriculture.Understanding the regulatory mechanisms that control gene expression in the rice genome is... Rice(Oryza sativa)is a staple food for more than half of the world's population and a critical crop for global agriculture.Understanding the regulatory mechanisms that control gene expression in the rice genome is fundamental for advancing agricultural productivity and food security.In mechanism,cis-regulatory elements(including promoters,enhancers,silencers,and insulators)are key DNA sequences whose activities determine the spatial and temporal expression patterns of nearby genes(Yocca and Edger,2022;Schmitz et al.,2022). 展开更多
关键词 cis regulatory elements deep learning chromatin profiles agricultural productivity rice genome cis regulatory sequence code gene expression food security
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Sequence and Molecular Evolution Analysis of Ubiquitin Proteins Encoded by Baculoviruses
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作者 郭忠建 朱颖敏 陈克平 《Agricultural Science & Technology》 CAS 2010年第9期53-57,共5页
[Objective] The aim of this study was to analyze the sequence characteristics and molecular evolution of ubiquitins encoded by baculoviruses.[Methods]Clustal W software was used for multiple sequence alignment analysi... [Objective] The aim of this study was to analyze the sequence characteristics and molecular evolution of ubiquitins encoded by baculoviruses.[Methods]Clustal W software was used for multiple sequence alignment analysis,and neighbor-joining method(NJ)and maximum parsimony method(MP)were used for the construction of phylogenetic tree.[Results]The baculoviral ubiquitins showed 73%-86% sequence identity to eukaryotic ubiquitin.Two heterogeneous regions of baculoviral ubiquitins were observed:one was the residues from 15-32,the other was located from residues 53 to 60.The else parts were conserved,where many functional amino acids were also observed.Phylogenetic analysis indicated that baculoviral ubiquitins could be divided into three sub-families,including sub-family GV,sub-family I and sub-family II.The molecular evolution of baculoviral ubiquitins might be under negative selection to maintain their functional and structural stability.[Conclusion]The analysis had provided reference for the researches on functional characterization of baculoviral ubiquitins. 展开更多
关键词 BACULOVIRUS UBIQUITIN sequence Molecular evolution
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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern 被引量:4
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作者 WANG Zhi1, 2, WU Li-xin1, 2, LI Hui-ying3 1. College of Resources and Civil Engineering, Northeastern University, Shenyang 110004, China 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, Beijing Normal University, Beijing 100875, China 3. College of Computer Science and Technology, Jilin University, Changchun 130012, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期570-576,共7页
Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navi... Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom. 展开更多
关键词 LIDAR codeD sequence pattern mobile POSITIONING SLAM ALGORITHM POSIT ALGORITHM
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The structural analysis of protein sequences based on the quasi-amino acids code 被引量:2
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作者 朱平 唐旭清 徐振源 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期363-369,共7页
Proteomics is the study of proteins and their interactions in a cell. With the successful completion of the Human Cenome Project, it comes the postgenome era when the proteomics technology is emerging. This paper stud... Proteomics is the study of proteins and their interactions in a cell. With the successful completion of the Human Cenome Project, it comes the postgenome era when the proteomics technology is emerging. This paper studies protein molecule from the algebraic point of view. The algebraic system (∑, +, *) is introduced, where ∑ is the set of 64 codons. According to the characteristics of (∑, +, *), a novel quasi-amino acids code classification method is introduced and the corresponding algebraic operation table over the set ZU of the 16 kinds of quasi-amino acids is established. The internal relation is revealed about quasi-amino acids. The results show that there exist some very close correlations between the properties of the quasi-amino acids and the codon. All these correlation relationships may play an important part in establishing the logic relationship between codons and the quasi-amino acids during the course of life origination. According to Ma F et al (2003 J. Anhui Agricultural University 30 439), the corresponding relation and the excellent properties about amino acids code are very difficult to observe. The present paper shows that (ZU, +,×) is a field. Furthermore, the operational results display that the eodon tga has different property from other stop codons. In fact, in the mitochondrion from human and ox genomic codon, tga is just tryptophane, is not the stop codon like in other genetic code, it is the case of the Chen W C et al (2002 Acta Biophysiea Siniea 18(1) 87). The present theory avoids some inexplicable events of the 20 kinds of amino acids code, in other words it solves the problem of 'the 64 codon assignments of mRNA to amino acids is probably completely wrong' proposed by Yang (2006 Progress in Modern Biomedicine 6 3). 展开更多
关键词 algebraic operation quasi-amino acids code protein sequences structural analysis
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GAUSS PERIODS AND CYCLIC CODES FROM CYCLOTOMIC SEQUENCES OF SMALL ORDERS 被引量:1
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作者 Hu Liqin Yue Qin Zhu Xiaomeng 《Journal of Electronics(China)》 2014年第6期537-546,共10页
Let p =ef +1 be an odd prime with positive integers e and f. In this paper, we calculate the values of Gauss periods of order e =3, 4, 6 over a finite field GF(q), where q is a prime with q≠p. As applications, severa... Let p =ef +1 be an odd prime with positive integers e and f. In this paper, we calculate the values of Gauss periods of order e =3, 4, 6 over a finite field GF(q), where q is a prime with q≠p. As applications, several cyclotomic sequences of order e =3, 4, 6 are employed to construct a number of classes of cyclic codes over GF(q) with prime length. Under certain conditions, the linear complexity and reciprocal minimal polynomials of cyclotomic sequences are calculated, and the lower bounds on the minimum distances of these cyclic codes are obtained. 展开更多
关键词 sequence Cyclic code Weight distribution Gauss period CYCLOTOMY
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Integrated Joint Source-Channel Symbol-by-Symbol Decoding of Variable-Length Codes Using 3-D MAP Sequence Estimation 被引量:1
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作者 WU Jing CHEN Shuzhen 《Wuhan University Journal of Natural Sciences》 CAS 2007年第3期471-475,共5页
Most of multimedia schemes employ variable-length codes (VLCs) like Huffman code as core components in obtaining high compression rates. However VLC methods are very sensitive to channel noise. The goal of this pape... Most of multimedia schemes employ variable-length codes (VLCs) like Huffman code as core components in obtaining high compression rates. However VLC methods are very sensitive to channel noise. The goal of this paper is to salvage as many data from the damaged packets as possible for higher audiovisual quality. This paper proposes an integrated joint source-channel decoder (I-JSCD) at a symbol-level using three-dimensional (3-D) trellis representation for first-order Markov sources encoded with VLC source code and convolutional channel code. This method combines source code and channel code state-spaces and bit-lengths to construct a two-dimensional (2-D) state-space, and then develops a 3-D trellis and a maximum a-posterior (MAP) algorithm to estimate the source sequence symbol by symbol. Experiment results demonstrate that our method results in significant improvement in decoding performance, it can salvage at least half of (50%) data in any channel error rate, and can provide additional error resilience to VLC stream like image, audio, video stream over high error rate links. 展开更多
关键词 integrated joint source-channel decoding (I-JSCD) variable-length code (VLC) exp-Golomb code convolutional code maximum a-oosteriori (MAP)
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Application of ITS2 Sequence as DNA Barcode in Xanthium 被引量:1
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作者 Xiaoyan ZHAO Weiyi HU 《Agricultural Biotechnology》 CAS 2014年第1期19-21,共3页
[ Objective ] Xanthium plants (non-Chinese species) are quarantine pests in China. This study aimed to distinguish and identify seven Xanthium spe- cies using ITS2 sequence as DNA barcode. [Method] ITS2 gene was amp... [ Objective ] Xanthium plants (non-Chinese species) are quarantine pests in China. This study aimed to distinguish and identify seven Xanthium spe- cies using ITS2 sequence as DNA barcode. [Method] ITS2 gene was amplified using universal primers to obtain ITS2 sequences of seven Xanthium species, which were then sequenced. ITS2 sequences of seven Xanthium species were compared and analyzed by MEGA 5.1 software, and the phylogenetic tree was constructed. [ Result] A total of 242 variable sites were found in 1TS2 sequences of Xanthium species, including 12 singleton variable sites. [ Conclusion] Xanthium species can be distinguished and identified based on ITS2 sequences. 展开更多
关键词 ITS2 sequence DNA barcede Xanthium
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Detailed oil-source correlation within the sequence and sedimentary framework in the Fushan Depression,Beibuwan Basin,South China Sea 被引量:1
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作者 Xin Wang Mei-Jun Li +3 位作者 Yang Shi Hao Guo Bang Zeng Xi He 《Petroleum Science》 2025年第1期90-109,共20页
The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nev... The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nevertheless,no systematic investigations on the classification and origin of oils and hy-drocarbon migration processes have been made for the entire petroleum system in this depression,which has significantly hindered the hydrocarbon exploration in the region.A total of 32 mudstone and 58 oil samples from the Fushan Depression were analyzed to definite the detailed oil-source correlation within the sequence and sedimentary framework.The organic matter of third member of Paleogene Liushagang Formation(Els(3))source rocks,both deltaic and lacustrine mudstone,are algal-dominated with high abundance of C_(23)tricyclic terpane and C_(30)4-methylsteranes.The deltaic source rocks occur-ring in the first member(Els_(1))and second member(Els_(2))of the Paleogene Liushagang Formation are characterized by high abundance of C_(19+20)tricyclic terpane and oleanane,reflecting a more terrestrial plants contribution.While lacustrine source rocks of Els_(1)and Els_(2)display the reduced input of terrige-nous organic matter with relatively low abundance of C 19+20 tricyclic terpane and oleanane.Three types of oils were identified by their biomarker compositions in this study.Most of the oils discovered in the Huachang and Bailian Els_(1)reservoir belong to group A and were derived from lacustrine source rocks of Els_(1)and Els_(2).Group B oils are found within the Els_(1)and Els_(2)reservoirs,showing a close relation to the deltaic source rocks of Els_(1)and Els_(2),respectively.Group C oils,occurring in the Els3 reservoirs,have a good affinity with the Els3 source rocks.The spatial distribution and accumulation of different groups of oils are mainly controlled by the sedimentary facies and specific structural conditions.The Els_(2)reservoir in the Yong'an area belonging to Group B oil,are adjacent to the source kitchen and could be considered as the favorable exploration area in the future. 展开更多
关键词 Oil-source correlation sequence stratigraphic framework Biomarkers Fushan depression South China Sea
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Progradational sequence stratigraphic architecture of the Triassic Yanchang Formation and a case study of Qingcheng Oilfield,Ordos Basin,NW China 被引量:1
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作者 HUI Xiao HOU Yunchao +2 位作者 QU Tong ZHANG Jie YANG Zhi 《Petroleum Exploration and Development》 2025年第5期1164-1178,共15页
To address the discrepancies between well and seismic data in stratigraphic correlation of the Triassic Yanchang Formation in the Ordos Basin,NW China,traditional stratigraphic classification schemes,the latest 3D sei... To address the discrepancies between well and seismic data in stratigraphic correlation of the Triassic Yanchang Formation in the Ordos Basin,NW China,traditional stratigraphic classification schemes,the latest 3D seismic and drilling data,and reservoir sections are thoroughly investigated.Guided by the theory of sequence stratigraphy,the progradational sequence stratigraphic framework of the Yanchang Formation is systematically constructed to elucidate new deposition mechanisms in the depressed lacustrine basin,and it has been successfully applied to the exploration and development practices in the Qingcheng Oilfield.Key findings are obtained in three aspects.First,the seismic progradational reflections,marker tuff beds,and condensed sections of flooding surfaces in the Yanchang Formation are consistent and isochronous.Using flooding surface markers as a reference,a progradational sequence stratigraphic architecture is reconstructed for the middle-upper part of Yanchang Formation,and divided into seven clinoform units(CF1-CF7).Second,progradation predominantly occurs in semi-deep to deep lake environments,with the depositional center not always coinciding with the thickest strata.The lacustrine basin underwent an evolution of“oscillatory regression-progradational infilling-multi-phase superimposition”.Third,the case study of Qingcheng Oilfield reveals that the major pay zones consist of“isochronous but heterochronous”gravity-flow sandstone complexes.Guided by the progradational sequence stratigraphic architecture,horizontal well oil-layer penetration rates remain above 82%.The progradational sequence stratigraphic architecture and associated geological insights are more consistent with the sedimentary infilling mechanisms of large-scale continental depressed lacustrine basins and actual drilling results.The research results provide crucial theoretical and technical support for subsequent refined exploration and development of the Yanchang Formation,and are expected to offer a reference for research and production practice in similar continental lacustrine basins. 展开更多
关键词 progradational sequence stratigraphic architecture CLINOFORM flooding surface continental depression lacustrine basin Ordos Basin TRIASSIC Yanchang Formation
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The Supplementary Motor Area as a Flexible Hub Mediating Behavioral and Neuroplastic Changes in Motor Sequence Learning:A TMS and TMS-EEG Study 被引量:1
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作者 Jing Chen Yanzi Fan +6 位作者 Xize Jia Fengmei Fan Jinhui Wang Qihong Zou Bing Chen Xianwei Che Yating Lv 《Neuroscience Bulletin》 2025年第5期837-852,共16页
Attempts have been made to modulate motor sequence learning(MSL)through repetitive transcranial magnetic stimulation,targeting different sites within the sensorimotor network.However,the target with the optimum modula... Attempts have been made to modulate motor sequence learning(MSL)through repetitive transcranial magnetic stimulation,targeting different sites within the sensorimotor network.However,the target with the optimum modulatory effect on neural plasticity associated with MSL remains unclarified.This study was therefore designed to compare the role of the left primary motor cortex and the left supplementary motor area proper(SMAp)in modulating MSL across different complexity levels and for both hands,as well as the associated neuroplasticity by applying intermittent theta burst stimulation together with the electroencephalogram and concurrent transcranial magnetic stimulation.Our data demonstrated the role of SMAp stimulation in modulating neural communication to support MSL,which is achieved by facilitating regional activation and orchestrating neural coupling across distributed brain regions,particularly in interhemispheric connections.These findings may have important clinical implications,particularly for motor rehabilitation in populations such as post-stroke patients. 展开更多
关键词 Motor sequence learning Intermittent theta burst stimulation Concurrent transcranial magnetic stimulation and electroencephalogram NEUROPLASTICITY Functional connectivity
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Bi-LSTM-Based Deep Stacked Sequence-to-Sequence Autoencoder for Forecasting Solar Irradiation and Wind Speed 被引量:1
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作者 Neelam Mughees Mujtaba Hussain Jaffery +2 位作者 Abdullah Mughees Anam Mughees Krzysztof Ejsmont 《Computers, Materials & Continua》 SCIE EI 2023年第6期6375-6393,共19页
Wind and solar energy are two popular forms of renewable energy used in microgrids and facilitating the transition towards net-zero carbon emissions by 2050.However,they are exceedingly unpredictable since they rely h... Wind and solar energy are two popular forms of renewable energy used in microgrids and facilitating the transition towards net-zero carbon emissions by 2050.However,they are exceedingly unpredictable since they rely highly on weather and atmospheric conditions.In microgrids,smart energy management systems,such as integrated demand response programs,are permanently established on a step-ahead basis,which means that accu-rate forecasting of wind speed and solar irradiance intervals is becoming increasingly crucial to the optimal operation and planning of microgrids.With this in mind,a novel“bidirectional long short-term memory network”(Bi-LSTM)-based,deep stacked,sequence-to-sequence autoencoder(S2SAE)forecasting model for predicting short-term solar irradiation and wind speed was developed and evaluated in MATLAB.To create a deep stacked S2SAE prediction model,a deep Bi-LSTM-based encoder and decoder are stacked on top of one another to reduce the dimension of the input sequence,extract its features,and then reconstruct it to produce the forecasts.Hyperparameters of the proposed deep stacked S2SAE forecasting model were optimized using the Bayesian optimization algorithm.Moreover,the forecasting performance of the proposed Bi-LSTM-based deep stacked S2SAE model was compared to three other deep,and shallow stacked S2SAEs,i.e.,the LSTM-based deep stacked S2SAE model,gated recurrent unit-based deep stacked S2SAE model,and Bi-LSTM-based shallow stacked S2SAE model.All these models were also optimized and modeled in MATLAB.The results simulated based on actual data confirmed that the proposed model outperformed the alternatives by achieving an accuracy of up to 99.7%,which evidenced the high reliability of the proposed forecasting. 展开更多
关键词 Deep stacked autoencoder sequence to sequence autoencoder bidirectional long short-term memory network wind speed forecasting solar irradiation forecasting
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Relationship between pore throat structure and crude oil mobility of full particle sequence reservoirs in Permian Fengcheng Formation,Mahu Sag,Junggar Basin,NW China 被引量:1
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作者 TANG Yong JIA Chengzao +8 位作者 CHEN Fangwen HE Wenjun ZHI Dongming SHAN Xiang YOU Xincai JIANG Lin ZOU Yang WU Tao XIE An 《Petroleum Exploration and Development》 2025年第1期112-124,共13页
Based on the experimental results of casting thin section,low temperature nitrogen adsorption,high pressure mercury injection,nuclear magnetic resonance T2 spectrum,contact angle and oil-water interfacial tension,the ... Based on the experimental results of casting thin section,low temperature nitrogen adsorption,high pressure mercury injection,nuclear magnetic resonance T2 spectrum,contact angle and oil-water interfacial tension,the relationship between pore throat structure and crude oil mobility characteristics of full particle sequence reservoirs in the Lower Permian Fengcheng Formation of Mahu Sag,Junggar Basin,are revealed.(1)With the decrease of reservoir particle size,the volume of pores connected by large throats and the volume of large pores show a decreasing trend,and the distribution and peak ranges of throat and pore radius shift to smaller size in an orderly manner.The upper limits of throat radius,porosity and permeability of unconventional reservoirs in Fengcheng Formation are approximately 0.7μm,8%and 0.1×10^(−3)μm^(2),respectively.(2)As the reservoir particle size decreases,the distribution and peak ranges of pores hosting retained oil and movable oil are shifted to a smaller size in an orderly manner.With the increase of driving pressure,the amount of retained and movable oil of the larger particle reservoir samples shows a more obvious trend of decreasing and increasing,respectively.(3)With the increase of throat radius,the driving pressure of reservoir with different particle levels presents three stages,namely rapid decrease,slow decrease and stabilization.The oil driving pressures of various reservoirs and the differences of them decrease with the increase of temperature and obviously decrease with the increase of throat radius.According to the above experimental analysis,it is concluded that the deep shale oil of Fengcheng Formation in Mahu Sag has great potential for production under geological conditions. 展开更多
关键词 Junggar Basin Mahu Sag Lower Permian Fengcheng Formation full particle sequence reservoir pore throat structure crude oil mobility whole petroleum system
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USING ERROR-CORRECTING ENCODERS TO DESIGN LOCAL-RANDOM SEQUENCE GENERATORS
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作者 杨义先 《Journal of Electronics(China)》 1995年第1期9-14,共6页
This paper proved the statement that a good linear block encoder is in fact a good local-random sequence generator. Furthermore, this statement discovers the deep relationship between the error-correcting coding theor... This paper proved the statement that a good linear block encoder is in fact a good local-random sequence generator. Furthermore, this statement discovers the deep relationship between the error-correcting coding theory and the modern cryptography. 展开更多
关键词 Error-correcting CODING CRYPTOGRAPHY RANDOM sequenceS
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Molecular Identification of Echinococcus spp. and Other Taeniid Tapeworms Using Next-Generation Sequence Analysis of PCR Amplified 18s rRNA Gene
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作者 Rasmi Abu-Helu George Kokaly +3 位作者 Sajeda Nojoum Imad Matouk Murad Ibrahim Ibrahim Abbasi 《American Journal of Molecular Biology》 2025年第1期75-87,共13页
Cystic echinococcosis (CE) is a prevalent zoonotic disease caused by Echinococcus granulosus, with a cosmopolitan distribution. The parasite is transmitted cyclically between canines and numerous intermediate herbivor... Cystic echinococcosis (CE) is a prevalent zoonotic disease caused by Echinococcus granulosus, with a cosmopolitan distribution. The parasite is transmitted cyclically between canines and numerous intermediate herbivorous livestock animals. Also, other Taeniid tapeworms could infect domestic dogs and they pose significant veterinary and public health concerns worldwide. This study aimed to develop a sensitive molecular method for detecting Echinococcus spp. DNA in dog fecal samples using next-generation sequencing (NGS). A set of PCR primers targeting conserved regions of Taeniid tapeworms’ 18s rRNA genes was designed and tested for amplifying genomic DNA from various tapeworm species. The PCR system demonstrated high sensitivity, amplifying DNA from all tested tapeworm species, with differences observed in amplified band sizes. The primers were adapted for NGS analysis by adding forward and reverse adapters, enabling the sequencing of amplified DNA fragments. Application of the developed PCR system to dog fecal samples collected from Yatta town, Palestine, revealed the presence of E. granulosus DNA in five out of 50 samples. NGS analysis confirmed the specificity of the amplified DNA fragments, showing 98% - 99% similarity with the 18s rDNA gene of E. granulosus. This study demonstrates the utility of NGS-based molecular methods for accurate and sensitive detection of Echinococcus spp. in dog fecal samples, providing valuable insights for epidemiological surveillance and control programs of echinococcosis in endemic regions. 展开更多
关键词 Cystic Echinococcosis Taeniid Tapeworms Next-Generation sequencing Molecular Detection Dog Fecal Samples
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The 2-adic complexity of sum sequences of Legendre sequences
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作者 JING Xiaoyan XU Zhefeng FENG Keqin 《纯粹数学与应用数学》 2025年第2期191-199,共9页
Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequenc... Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequence of any k many Legendre sequences and show that the 2-adic complexity of the sum sequences of any k many Legendre sequences reaches the maximum by proving the case of k=2 and 3,which implies that the sum sequences can resist the attack of rational approximation algorithm. 展开更多
关键词 2-adic complexity binary sequences Legendre symbol Legendre sequences
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THE APPLICATION OF LINEAR COMPLEXITY OF SEQUENCES TO LOWER BOUNDS ON THE MINIMUM DISTANCE OF CYCLIC CODES
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作者 李元兴 粱传甲 《Journal of Electronics(China)》 1990年第4期312-316,共5页
Firstly,the Fourier transforms in finite fields and the concept of linear complexityof sequences are described.Then several known lower bounds on the minimum distance of cycliccodes are outlined.Finally,the minimum di... Firstly,the Fourier transforms in finite fields and the concept of linear complexityof sequences are described.Then several known lower bounds on the minimum distance of cycliccodes are outlined.Finally,the minimum distance of cyclic codes is analyzed via linear complexityof sequences,and new theorems about the lower bounds are obtained. 展开更多
关键词 CYCLIC codeS Linear COMPLEXITY FOURIER transforms
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PLC transition sequence identification based on logical reduction
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作者 Yue Luo Jianhong Ye +2 位作者 Jiazhong Zhou Jia Liu Linping Jiang 《Control Theory and Technology》 2025年第4期672-687,共16页
In industrial control systems,such as power transmission facilities and water treatment plants,Programmable Logic Controllers(PLCs)can work consistently and stably over long periods if there are no faults.Black-box id... In industrial control systems,such as power transmission facilities and water treatment plants,Programmable Logic Controllers(PLCs)can work consistently and stably over long periods if there are no faults.Black-box identification aims to automatically construct Petri net models with the help of I/O signals from PLC devices only.The main challenge is how to convert the infinitely long PLC signals into an event sequence,which is the foundation for subsequent modeling.The current algorithms are confronted with a number of challenges,including an exponential increase in the number of transitions,high time complexity,and susceptibility to noisy signals.To solve these problems,this paper proposes a new method for converting PLC signals into a transition sequence.The method is based on the principles of Boolean absorption law,which filters out noise information in the I/O signals.Then firing functions representing input–output causality are constructed from the filtered signals.Finally,the original signal sequence is traversed to generate a transition sequence.The experimental results show that these methods can rapidly identify a transition sequence.Compared to traditional methods,the proposed algorithms have polynomial time complexity. 展开更多
关键词 PLC Boolean logic Transition sequence Petri net
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POWER CONTROL WITH CODER-ESTIMATOR SEQUENCES
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作者 Li Xia Wong Wing Shing(Dept. of Electrical Engineering, Shenzhen University, Shenzhen 518060) (Dept. of Information Engineering, the Chinese University of Hong Kong, Shatin, N.T., Hong Kong) 《Journal of Electronics(China)》 1999年第3期263-268,共6页
Power control is an important issue in mobile communication systems and has been studied extensively in the literature. This paper has taken on a new perspective and modeled the problem as a state estimation problem w... Power control is an important issue in mobile communication systems and has been studied extensively in the literature. This paper has taken on a new perspective and modeled the problem as a state estimation problem with finite communication constraints. The problem is solved by using the 1-bit mean coder-estimator sequence. The performance of the coder-estimator sequence is compared with that of the simple feedback power control technique by evaluating their respective fade margins as in commonly done in radio system engineering. 展开更多
关键词 MOBILE communication Power control coder-estimator sequence
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Unsupervised hierarchical sequence stratigraphy framework of carbonate successions
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作者 Márcio Vinicius Santana Dantas Kaio Henrique Masse Vieira +9 位作者 Thomás Jung Spier JoséArthur Oliveira Santos Alan Cabral Trindade Prado Danilo Vomlel Mariana Leite Felipe Alves Farias Daniel Galvão Carnier Fragoso Humberto Reis Gabriel Coutinho Douglas G.Macharet 《Artificial Intelligence in Geosciences》 2025年第2期306-319,共14页
Performing the high-resolution stratigraphic analysis may be challenging and time-consuming if one has to work with large datasets.Moreover,sedimentary records have signals of different frequencies and intrinsic noise... Performing the high-resolution stratigraphic analysis may be challenging and time-consuming if one has to work with large datasets.Moreover,sedimentary records have signals of different frequencies and intrinsic noise,resulting in a complex signature that is difficult to identify only through eyes-based analysis.This work proposes identifying transgressive-regressive(T-R)sequences from carbonate facies successions of three South American basins:(i)São Francisco Basin-Brazil,(ii)Santos Basin-Brazil,and(iii)Salta Basin-Argentina.We applied a hidden Markov model in an unsupervised approach followed by a Score-Based Recommender System that automatically finds medium or low-frequency sedimentary cycles from high-frequency ones.Our method is applied to facies identified using Fullbore Formation Microimager(FMI)logs,outcrop description,and composite logs from carbonate intervals.The automatic recommendation results showed better long-distance correlations between medium-to low-frequency sedimentary cycles,whereas the hidden Markov model method successfully identified high-resolution(high-frequency)transgressive and regressive systems tracts from the given facies successions.Our workflow offers advances in the automated analyses and construction of to lower-higher-rank stratigraphic framework and short to long-distance stratigraphic correlation,allowing for scale large-automated processing of the basin dataset.Our approach in this work fits the unsupervised learning framework,as we require no previous input of stratigraphical analysis in the basin.The results provide solutions for prospecting any sediment-hosted mineral resource,especially for the oil and gas industry,offering support for subsurface geological characterization,whether at the exploration scale or for reservoir zoning during production development. 展开更多
关键词 sequence stratigraphy High-frequency cycles Markov chain Unsupervised learning
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Optimization of Linear Sequence-controlled Copolymers for Maximizing Adsorption Capacity
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作者 Sheng-Da Zhao Qiu-Ju Chen +2 位作者 Zhi-Xin Liu Quan-Xiao Dong Xing-Hua Zhang 《Chinese Journal of Polymer Science》 2025年第10期1739-1748,共10页
The optimization of polymer structures aims to determine an optimal sequence or topology that achieves a given target property or structural performance.This inverse design problem involves searching within a vast com... The optimization of polymer structures aims to determine an optimal sequence or topology that achieves a given target property or structural performance.This inverse design problem involves searching within a vast combinatorial phase space defined by components,se-quences,and topologies,and is often computationally intractable due to its NP-hard nature.At the core of this challenge lies the need to evalu-ate complex correlations among structural variables,a classical problem in both statistical physics and combinatorial optimization.To address this,we adopt a mean-field approach that decouples direct variable-variable interactions into effective interactions between each variable and an auxiliary field.The simulated bifurcation(SB)algorithm is employed as a mean-field-based optimization framework.It constructs a Hamiltonian dynamical system by introducing generalized momentum fields,enabling efficient decoupling and dynamic evolution of strongly coupled struc-tural variables.Using the sequence optimization of a linear copolymer adsorbing on a solid surface as a case study,we demonstrate the applica-bility of the SB algorithm to high-dimensional,non-differentiable combinatorial optimization problems.Our results show that SB can efficiently discover polymer sequences with excellent adsorption performance within a reasonable computational time.Furthermore,it exhibits robust con-vergence and high parallel scalability across large design spaces.The approach developed in this work offers a new computational pathway for polymer structure optimization.It also lays a theoretical foundation for future extensions to topological design problems,such as optimizing the number and placement of side chains,as well as the co-optimization of sequence and topology. 展开更多
关键词 Combinatorial optimization Optimal design sequence design COPOLYMER Adsorption problem
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