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Constructions of Control Sequence Set for Hierarchical Access in Data Link Network
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作者 Niu Xianhua Ma Jiabei +3 位作者 Zhou Enzhi Wang Yaoxuan Zeng Bosen Li Zhiping 《China Communications》 2026年第1期67-80,共14页
As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and ... As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and diverse communication needs.It is crucial to design control sequences with robust randomness and conflict-freeness to properly address differentiated access control in data link.In this paper,we propose a hierarchical access control scheme based on control sequences to achieve high utilization of time slots and differentiated access control.A theoretical bound of the hierarchical control sequence set is derived to characterize the constraints on the parameters of the sequence set.Moreover,two classes of optimal hierarchical control sequence sets satisfying the theoretical bound are constructed,both of which enable the scheme to achieve maximum utilization of time slots.Compared with the fixed time slot allocation scheme,our scheme reduces the symbol error rate by up to 9%,which indicates a significant improvement in anti-interference and eavesdropping capabilities. 展开更多
关键词 control sequence data link hierarchical access control theoretical bound
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A New Construction of Stefan’s Homological Spectral Sequence
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作者 LIU Li-yu 《Chinese Quarterly Journal of Mathematics》 2026年第1期60-67,共8页
In this paper,we offer a new construction of Stefan’s homological spectral sequence for Hopf Galois extensions,by using the double complex argument.Under the faithfully flat condition,a method for computation of Hoch... In this paper,we offer a new construction of Stefan’s homological spectral sequence for Hopf Galois extensions,by using the double complex argument.Under the faithfully flat condition,a method for computation of Hochschild homology is given. 展开更多
关键词 Hopf algebra Hopf Galois extension Spectral sequence Hochschild homology
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Sedimentary Characteristics and Evolution of the High-resolution Sequence Stratigraphic Framework of the Taiyuan Formation in the Hangjinqi Area,Northern Ordos Basin
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作者 ZHAO Mingsheng TIAN Jingchun +1 位作者 SU Bingrui ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 2026年第1期54-68,共15页
The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theor... The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theoretical and practical significance for guiding oil and gas exploration.The sedimentary facies and sedimentary evolution of the high-resolution sequence framework of the Carboniferous Taiyuan Formation in the Hangjinqi area have been systematically analyzed for the first time by drilling,logging and seismic data.The results show that four types of sequence interfaces can be identified in the Taiyuan Formation:regional unconformity surfaces,scour surfaces,lithologic-lithofacies transformation surfaces and flooding surfaces.According to the sedimentary response caused by the upward and downward movements of the base level at different levels,the Taiyuan Formation can be divided into 2 long-term cycles(LSC_(1)-LSC_(2)),4 mid-term cycles(MSC_(1)-MSC4)and 7 short-term cycles(SSC_(1)-SSC7).The long-and mid-term cycles correspond to members T_(1)and T_(2)and layers T_(1)-1,T_(1-2),T_(2-1),and T_(2)-2,respectively.Long-term cycles are dominated by C_(1);mid-term cycles are dominated by C_(1)and C_(2),followed by A2;and short-term cycles are dominated by C_(1),C_(2),A1 and A2.Under the high-resolution sequence stratigraphic framework,the Hangjinqi area underwent a transformation of fan delta and tidal flat depositional systems during the Taiyuan Formation sedimentary period.In the MSC_(1)-MSC_(2)stage,owing to a large-scale paleocontinent,the fan delta sedimentary body,which was limited in scale and scope,developed only in the southeastern corner and gradually transitioned basinward to tidal flat facies.In the MSC3-MSC4 stage,as the paleocontinent continuously decreased and the sedimentary range expanded,fan-delta plain sedimentation began in the study area.Several braided distributary channels with poor connectivity developed on the fan-delta plain,and between them were floodplains and peat swamps. 展开更多
关键词 high-resolution sequence framework sedimentary characteristics sedimentary evolution Taiyuan Formation Hangjinqi area northern Ordos Basin
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Genetic diversity and population structure of the Fujian oyster Crassostrea angulata revealed by mitochondrial COI gene and nuclear gene ITS2 sequences
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作者 Shiqi YU Ziqiang HAN Huayong QUE 《Journal of Oceanology and Limnology》 2026年第1期419-432,共14页
The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The mai... The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata. 展开更多
关键词 Crassostrea angulata genetic diversity population structure mitochondrial COⅠgene nuclear gene ITS2 sequence
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Robust Hyper-Polarization Protocol of Nuclear Spins via Magic Sequence
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作者 Haiyang Li Yongju Li +1 位作者 Hao Liao Ping Wang 《Chinese Physics Letters》 2026年第1期105-128,共24页
Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to thei... Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to their small gyromagnetic ratios.A promising approach to achieving high nuclear spin polarization is transferring the polarization of electrons to nuclear spins.The nitrogen-vacancy(NV)center in diamond has emerged as a highly effective medium for this purpose,and various hyperpolarization protocols have been developed.Among these,the pulsed polarization(PulsePol)method has been extensively studied due to its robustness against static energy shifts of the electron spin.In this work,we present a novel polarization protocol and uncover a family of magic sequences for hyperpolarizing nuclear spins,with PulsePol emerging as a special case of our general approach.Notably,we demonstrate that some of these magic sequences exhibit significantly greater robustness compared to the PulsePol protocol in the presence of finite half𝜋pulse duration of the protocol,Rabi and detuning errors.This enhanced robustness positions our protocol as a more suitable candidate for hyper-polarizing nuclear spins species with large gyromagnetic ratios and also ensures better compatibility with high-efficiency readout techniques at high magnetic fields.Additionally,the generality of our protocol allows for its direct application to other solid-state quantum systems beyond the NV center. 展开更多
关键词 transferring polarization electrons hyperpolarization protocols quantum information technologiesas nuclear spins pulse polarization nuclear spin polarization magic sequences nuclear magnetic resonance
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Stochastic discrete event simulation for government assisted owner driven participatory housing recovery modeling:Application to 2015 Gorkha earthquake sequence,Nepal
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作者 Dipendra Gautam Sajan KC Olafur Petur Palsson 《Resilient Cities and Structures》 2026年第1期45-59,共15页
We develop and implement a Stochastic Discrete Event Simulation(SDES)algorithm to model the housing re-covery trajectory after an extreme event.The algorithm models discrete events and their underlying uncertainties i... We develop and implement a Stochastic Discrete Event Simulation(SDES)algorithm to model the housing re-covery trajectory after an extreme event.The algorithm models discrete events and their underlying uncertainties in each construction phase.Specifically,the algorithm is developed for the Government Assisted Owner Driven(GAOD)reconstruction system to simulate long-term recovery trajectory.SDES,as a flexible modeling approach,can simulate any housing recovery scenario that follows phased reconstruction.The 2015 M 7.8 Gorkha earthquake sequence in Nepal is considered the extreme event,with 796,245 buildings requiring reconstruction.We present some recovery trajectories from severely hit,crisis hit,and earthquake hit parishes,comparing them with the actual reconstruction progress.We also assess quality and improvement of reconstructed buildings using seismic fragility functions,compared to pre-earthquake constructions.Housing recovery uncertainties are dissected in relation to reconstruction pace.We conclude that the vast majority of the reconstructed buildings followed the Build Back Better(BBB)approach and missed the opportunity to pursue the Build Back Resilient(BBR)approach due to multifaceted challenges ranging from unclear policies to economic constraints.We critically assess the GAOD vs Owner Driven(OD)recovery framework and conclude that insurance-supported and technically assisted OD approach could be the most suitable model for post extreme event housing recovery. 展开更多
关键词 Stochastic modeling Discrete event simulation Participatory reconstruction Housing recovery Community resilience Earthquake damage Reinforced concrete Stone masonry Brick masonry Seismic vulnerability Gorkha earthquake sequence
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基于FPGA的高带宽FCS计算设计与实现
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作者 李治辉 许芮铭 《无线互联科技》 2025年第10期102-105,共4页
文章深入探讨了基于现场可编程门阵列(Field-Programmable Gate Array,FPGA)实现高带宽帧校验序列(Frame Check Sequence,FCS)计算方法。阐述了高带宽FCS计算在现代高速数据通信系统中的关键意义,详细介绍了基于FPGA的实现方案,涵盖循... 文章深入探讨了基于现场可编程门阵列(Field-Programmable Gate Array,FPGA)实现高带宽帧校验序列(Frame Check Sequence,FCS)计算方法。阐述了高带宽FCS计算在现代高速数据通信系统中的关键意义,详细介绍了基于FPGA的实现方案,涵盖循环冗余校验-32(Cyclic Redundancy Check-32,CRC-32)计算算法优化、硬件架构设计以及实现验证等环节。通过实验验证,该方法显著提升了FCS计算带宽,能有效满足高速数据传输场景下对数据完整性校验的严苛要求。 展开更多
关键词 FPGA 高带宽 fcs计算 CRC-32 数据通信
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ON THE LINEAR COMPLEXITY OF FCSR SEQUENCES 被引量:2
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作者 Qi Wenfeng Xu HongDept of Appl.Math,Zhengzhou Information Engineering Univ., Zhengzhou 450002,China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第3期318-324,共7页
The linear complexity of a new kind of keystream sequences.FCSR sequences,is discussed by use of the properties of cyclotomic polynomials.Based on the results of C.Seo's,an upper bound and a lower bound on the li... The linear complexity of a new kind of keystream sequences.FCSR sequences,is discussed by use of the properties of cyclotomic polynomials.Based on the results of C.Seo's,an upper bound and a lower bound on the linear complexity of a significant kind of FCSR sequences—l-sequences are presented. 展开更多
关键词 linear recurring sequence feedback with carry shift register l-sequences linear complexity
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PLC transition sequence identification based on logical reduction 被引量:1
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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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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:4
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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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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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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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基于FCS-MPC的凝结水泵电机变频控制方法 被引量:2
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作者 苏飞 《微特电机》 2025年第1期65-69,共5页
面对复杂多变的火力发电机组运行环境,凝结水泵运行需求增大,但是稳定性不足。研究一种基于有限集模型预测控制的水泵电机变频控制方法。设计价值函数及期望值,将价值函数最小化作为目标函数,将变频控制过程转换为优化求解过程;利用飞... 面对复杂多变的火力发电机组运行环境,凝结水泵运行需求增大,但是稳定性不足。研究一种基于有限集模型预测控制的水泵电机变频控制方法。设计价值函数及期望值,将价值函数最小化作为目标函数,将变频控制过程转换为优化求解过程;利用飞蛾扑火优化算法,在控制输入空间内寻求使得价值函数最小的最优控制输入,应用到凝结水泵控制系统中;通过变频器实现凝结水泵电机变频控制。结果表明,超调量在不同时刻均保持在相对较低的水平,凝结水泵电机变频控制的稳定性较好,可以应对复杂多变的火电机组运行环境。 展开更多
关键词 有限集模型预测控制 火电机组 凝结水泵 状态反馈量 价值函数 变频控制方法
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Knockout of the fcsk gene in zebrafish causes neurodevelopmental defects
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作者 Zhen-Xing Liu Ting-Ting Zou +2 位作者 Hui-Hui Liu Hai-Bo Jia Xian-Qin Zhang 《Zoological Research》 2025年第2期313-324,共12页
Congenital disorders of glycosylation(CDG)are a cluster of monogenic disorders resulting from defects in glycosylation.FCSK encodes fucokinase,an enzyme that catalyzes the phosphorylation of L-fucose to generate fucos... Congenital disorders of glycosylation(CDG)are a cluster of monogenic disorders resulting from defects in glycosylation.FCSK encodes fucokinase,an enzyme that catalyzes the phosphorylation of L-fucose to generate fucose-1-phosphate,an important step in fucosylation.Mutations in FCSK lead to CDG with an autosomal recessive inheritance pattern,primarily manifesting as developmental delay,hypotonia,and brain abnormalities.However,no fcsk mutant animal models have yet been established.This study constructed the first fcsk knockout(fcsk^(-/-))zebrafish model using CRISPR/Cas9 technology.Notably,fcsk^(-/-)zebrafish exhibited impaired growth,characterized by delayed epiboly and DNA accumulation during early embryonic development,as well as brain atrophy in adulthood.Larval-stage fcsk^(-/-)zebrafish displayed locomotor deficits and increased susceptibility to pentylenetetrazole-induced seizures.In adulthood,fcsk^(-/-)zebrafish showed neurodevelopmental abnormalities,including increased anxiety,decreased aggression,reduced social preference,and impaired memory.Additionally,total protein fucosylation was markedly reduced in fcsk^(-/-)zebrafish,accompanied by decreased expression of pofut2,which encodes protein Ofucosyltransferase 2,an enzyme involved in the fucosylation salvage pathway.Apoptotic activity was elevated in the midbrain-hindbrain boundary(MHB)of fcsk^(-/-)zebrafish.Supplementation with GDP-L-fucose or the human FCSK gene restored developmental defects and total protein fucosylation in fcsk^(-/-)zebrafish.RNA sequencing revealed dysregulated gene expression associated with glycosylation,apoptosis,and neurodegenerative diseases.These findings suggest that fcsk^(-/-)zebrafish exhibit neurodevelopmental disorders,providing the first fcsk gene knockout animal model and offering a platform for investigating the molecular underpinnings of the disease and facilitating drug screening efforts. 展开更多
关键词 Congenital disorders of glycosylation fcsk ZEBRAFISH BEHAVIOR RNA sequencing
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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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Bayesian-based analysis of sequence activity characteristics in the Bohai Rim region
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作者 Bi Jin-Meng Song Cheng Cao Fu-Yang 《Applied Geophysics》 2025年第2期237-251,554,共16页
Disaster mitigation necessitates scientifi c and accurate aftershock forecasting during the critical 2 h after an earthquake. However, this action faces immense challenges due to the lack of early postearthquake data ... Disaster mitigation necessitates scientifi c and accurate aftershock forecasting during the critical 2 h after an earthquake. However, this action faces immense challenges due to the lack of early postearthquake data and the unreliability of forecasts. To obtain foundational data for sequence parameters of the land-sea adjacent zone and establish a reliable and operational aftershock forecasting framework, we combined the initial sequence parameters extracted from envelope functions and incorporated small-earthquake information into our model to construct a Bayesian algorithm for the early postearthquake stage. We performed parameter fitting and early postearthquake aftershock occurrence rate forecasting and effectiveness evaluation for 36 earthquake sequences with M ≥ 4.0 in the Bohai Rim region since 2010. According to the results, during the early stage after the mainshock, earthquake sequence parameters exhibited relatively drastic fl uctuations with signifi cant errors. The integration of prior information can mitigate the intensity of these changes and reduce errors. The initial and stable sequence parameters generally display advantageous distribution characteristics, with each parameter’s distribution being relatively concentrated and showing good symmetry and remarkable consistency. The sequence parameter p-values were relatively small, which indicates the comparatively slow attenuation of signifi cant earthquake events in the Bohai Rim region. A certain positive correlation was observed between earthquake sequence parameters b and p. However, sequence parameters are unrelated to the mainshock magnitude, which implies that their statistical characteristics and trends are universal. The Bayesian algorithm revealed a good forecasting capability for aftershocks in the early postearthquake period (2 h) in the Bohai Rim region, with an overall forecasting effi cacy rate of 76.39%. The proportion of “too low” failures exceeded that of “too high” failures, and the number of forecasting failures for the next three days was greater than that for the next day. 展开更多
关键词 earthquake sequences Bayesian algorithm model parameters correlation analysis effectiveness evaluation
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Sequence stratigraphy and sedimentary evolution from Late Cretaceous to Quaternary in the Romney 3D seismic area,deep-water Taranaki Basin(New Zealand)
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作者 Guang-Xu Wang Wei Wu +4 位作者 Quan Li Wei-Qing Liu Yong-Sheng Zhou Shi-Qin Liang Ya-Ping Sui 《Petroleum Science》 2025年第5期1854-1875,共22页
The study of sequence stratigraphy often focuses on shallow marine and shelf-edge regions,while research on deep-sea stratigraphic sequences remains relatively weak.This study,based on highresolution 3D seismic data a... The study of sequence stratigraphy often focuses on shallow marine and shelf-edge regions,while research on deep-sea stratigraphic sequences remains relatively weak.This study,based on highresolution 3D seismic data and drilling information,utilized sequence stratigraphy and seismic sedimentology as guidelines,and employed seismic interpretation methods to performed a division of deepsea stratigraphic sequences within the Romney 3D seismic survey area in the deep-water Taranaki Basin,New Zealand.Furthermore,it analyzed the characteristics of typical depositional systems and their associated controlling factors.The findings are as follows:(1)Based on seismic reflection termination relationships and seismic facies characteristics,four second-order sequence boundaries and nine thirdorder sequence boundaries were identified,resulting in the delineation of three second-order sequences and twelve third-order sequences in the basin.(2)Five seismic facies were recognized,corresponding to five typical sedimentary bodies:mass transport deposits(MTDs),deep-water channel,levee deposits,deltaic deposits,and pelagic deposits.However,due to the relatively thin sedimentary thickness of carbonate sediments,the seismic facies characteristics of carbonate sediments cannot be discerned in seismic data,but can be identified based on well data.Deltaic sediments mainly developed during the rift stage of the basin,while carbonate sediments formed during the transition from a passive to an active margin.Deep-water channel and levee deposits and MTDs emerged during the active margin stage,while pelagic deposits are ubiquitous in marine environments.(3)The uplift of New Zealand's interior and climate-driven erosion caused the resurgence of clastic sediments,which began to be transported to the deep sea,the seafloor topography would directly affect the movement path of sediment gravity flow,and sediment supply can affect the development and evolution of sedimentary systems.(4)Event deposits boundaries,such as erosional scour surfaces formed by channels and unconformities created by MTDs,can serve as boundaries for the division of deep-water stratigraphic sequences.This study proposes a method for delineating deep-water stratigraphic sequences using event deposits,particularly suitable under conditions where the influence of relative sea-level changes on deep-water deposits is relatively weak.This research not only enhances the understanding of deep-water depositional sequences but also provides a reference for studies on the evolution of deep-water deposition and its controlling factors in research areas with similar geological backgrounds worldwide. 展开更多
关键词 sequence stratigraphy Seismicfacies Sedimentary systemevolution Genesismechanism Sedimentsupply Deep-water Taranaki Basin
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