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Early and accurate diagnosis and selection of appropriate treatment plans are crucial for patients with gastrointestinal hemangiomas
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作者 Zhou Chen Liang Wang Peng-Jie Yu 《World Journal of Gastrointestinal Surgery》 2025年第2期303-307,共5页
Gastrointestinal hemangioma(GIH)is clinically rare,accounting for 7%-10%of benign gastrointestinal tumors and 0.5%of systemic hemangiomas.GIH can occur as either solitary or multiple lesions,with gastrointestinal blee... Gastrointestinal hemangioma(GIH)is clinically rare,accounting for 7%-10%of benign gastrointestinal tumors and 0.5%of systemic hemangiomas.GIH can occur as either solitary or multiple lesions,with gastrointestinal bleeding as a significant clinical manifestation.Understanding the clinical and endoscopic features of GIH is essential for improving diagnostic accuracy,particularly through endoscopy and selective arteriography,which are highly effective in diagnosing GIH and preventing misdiagnosis and inappropriate treatment.Upon confirmed diagnosis,it is essential to thoroughly evaluate the patient's condition to determine the most suitable treatment modality—whether surgical,endoscopic,or minimally invasive intervention.The minimally invasive interventional partial embolization therapy using polyvinyl alcohol particles,proposed and implemented by Pospisilova et al,has achieved excellent clinical outcomes.This approach reduces surgical trauma and the inherent risks of traditional surgical treatments. 展开更多
关键词 HEMANGIOMA Gastrointestinal hemangioma Gastrointestinal hemorrhage Minimally invasive interventional treatment Selective embolization
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急性肺栓塞患者外周血循环ACE2和Mas表达及其对内皮损伤的影响
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作者 许东明 刘昶 +1 位作者 周杰 肖红丽 《西部医学》 2025年第1期48-53,共6页
目的探究急性肺栓塞(APE)患者治疗前后外周血循环内皮细胞(CECs)凋亡数量及ACE2、Mas蛋白表达变化。方法收集2023年1月—2023年10月本院急诊科接收的APE患者82例,根据疾病严重程度将其分为中高危组42例、低危组40例,另选取40例于本院体... 目的探究急性肺栓塞(APE)患者治疗前后外周血循环内皮细胞(CECs)凋亡数量及ACE2、Mas蛋白表达变化。方法收集2023年1月—2023年10月本院急诊科接收的APE患者82例,根据疾病严重程度将其分为中高危组42例、低危组40例,另选取40例于本院体检的健康受试者为对照组。取APE患者入院时、出院时及健康受试者外周血。流式细胞术分析APE患者及健康受试者CECs数量、凋亡水平。Western blotting检测CECs内凋亡蛋白Bax、Bcl2、caspase 3/9水平变化及蛋白ACE2、Mas表达变化。结果入院时中高危组、低危组患者入院时外周血CECs数量及凋亡率均显著高于对照组,且中高危组CECs数量及凋亡率均显著高于低危组水平(P<0.05)。出院时中高危组及低危组患者CECs数量及凋亡率均显著低于入院时水平(P<0.05)。入院时中高危组、低危组患者CECs中Bax/Bcl2蛋白比值、切割caspase 3/9蛋白水平显著高于对照组,且中高危组这些指标水平显著高于低危组,同时出院时中高危组、低危组患者CECs上述指标水平显著低于入院时水平(P<0.05)。进一步发现入院时中高危组、低危组CECs中ACE2、Mas水平显著低于对照组,且中高危组上述指标水平显著低于低危组(P<0.05)。结论APE患者外周血CECs数量及凋亡率显著增加,治疗后CECs数量及凋亡率减少,提示CECs可能与APE发病及预后相关,同时ACE2-Mas轴可能参与调控CECs凋亡。 展开更多
关键词 急性肺栓塞 循环内皮细胞 凋亡 血管紧张素转化酶2 mas
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Antenna Selection and Power Allocation Design for 5G Massive MIMO Uplink Networks 被引量:10
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作者 Hongyuan Gao Yumeng Su +1 位作者 Shibo Zhang Ming Diao 《China Communications》 SCIE CSCD 2019年第4期1-15,共15页
Massive MIMO is one of the key technologies in future 5G communications which can satisfy the requirement of high speed and large capacity. This paper considers antenna selection and power allocation design to promote... Massive MIMO is one of the key technologies in future 5G communications which can satisfy the requirement of high speed and large capacity. This paper considers antenna selection and power allocation design to promote energy conservation then provide good quality of service(QoS) for the whole massive MIMO uplink network. Unlike previous related works, hardware impairment, transmission efficiency, and energy consumption at the circuit and antennas are involved in massive MIMO networks. In order to ensure the QoS, we consider the minimum rate constraint for each user and the system, which increases the complexity of power allocation problem for maximizing energy and spectral efficiency in massive MIMO system. To this end, a quantum-inspired social emotional optimization(QSEO) algorithm is proposed to obtain the optimal power control strategy in massive MIMO uplink networks. Simulation results assess the great advantages of QSEO which previous strategies do not have. 展开更多
关键词 5G masSIVE MIMO antenna selection power ALLOCATION quantum-inspiredsocial EMOTIONAL optimization
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Probe Selection for Over-the-Air Test in 5G Base Stations with Massive Multiple-Input Multiple-Output 被引量:5
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作者 Xiang Zhang Shangbin Qiao +1 位作者 Mugen Peng Yong Li 《China Communications》 SCIE CSCD 2019年第7期1-12,共12页
In 5G systems, massive multiple-input multiple-output (MIMO) has been adopted in base stations (BSs) to improve spectral efficiency and coverage. The traditional conductive performance test techniques are challenging ... In 5G systems, massive multiple-input multiple-output (MIMO) has been adopted in base stations (BSs) to improve spectral efficiency and coverage. The traditional conductive performance test techniques are challenging due to the unaffordable cost and high complexity when testing a large number of antennas. To solve this problem, the over-the-air (OTA) test has been presented, in which probe selection is the key to reduce the number of channel emulators and probes. In this paper, a novel artificial bee colony (ABC) algorithm is introduced to enhance the efficiency and accuracy of probe selection procedure. A sectoring- based multi-probe anechoic chamber (MPAC) is built to evaluate the throughput performance of massive MIMO equipped in 5G BS. In addition, link level simulation is carried out to evaluate the proposal’s performance gain under the commercial network assumptions, where the average throughput of three velocity is given with different SNR region. The results suggest that OTA chamber and multi-probe wall are available not only for 5G BSs, but also for user equipments (UEs) with end-to-end communication. 展开更多
关键词 anechoic chamber masSIVE MIMO base stations over-the-air TEST PROBE selection performance evaluation
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Mass Selection for Growth Improvement in Black Shell Line of Pacific Oyster Crassostrea gigas 被引量:3
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作者 XU Chengxun LI Qi +2 位作者 CHONG Jindou LIU Shikai KONG Lingfeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第6期1411-1416,共6页
The Pacific oyster,Crassostrea gigas,naturally distributing along the coast of northwest Pacific,is one of the most important bivalve species due to its high economic value and fecundity.In China,we have initiated a s... The Pacific oyster,Crassostrea gigas,naturally distributing along the coast of northwest Pacific,is one of the most important bivalve species due to its high economic value and fecundity.In China,we have initiated a selective breeding program on both shell color and growth rate of C.gigas since 2010.A black shell line was obtained through four-generation family selection.In this study,mass selection for growth improvement was conducted in the sixth generation and seventh generation of black shell lines.To assess the progress of potential genetic improvement,the progeny of two generations of black shell lines were selected to evaluate their shell heights via a 450-day farming experiment.As the results,after growing for 450 days,the sixth generation and seventh generation of selected lines were 9.03% and 11.42% larger than the control lines,respectively.During the grow-out stage,the genetic gain of two generations was 8.82%±0.18% and 11.54%±0.43%,respectively;and the corresponding realized heritability was 0.45±0.04 and 0.41±0.04,respectively.These results indicated that the mass selection for shell height achieved steady progress in the two generations of C.gigas. 展开更多
关键词 Pacific OYSTER CRASSOSTREA GIGAS mass selection black shell LINE genetic gain realized HERITABILITY
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Fine mapping and marker-assisted selection (MAS) of a low glutelin content gene in rice 被引量:18
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作者 Yi Hua WANG Shi Jia LIU +4 位作者 Su Lan JI Wen Wei ZHANG Chun Ming WANG Ling JIANG Jian Min WAN 《Cell Research》 SCIE CAS CSCD 2005年第8期622-630,共9页
Rice with low glutelin content is suitable as functional food for patients affected with diabetes and kidney failure. The fine mapping of the gene(s) responsible for low glutelin content will provide information regar... Rice with low glutelin content is suitable as functional food for patients affected with diabetes and kidney failure. The fine mapping of the gene(s) responsible for low glutelin content will provide information regarding the distribution of glutelin related genes in rice genome and will generate markers for the selection of low glutelin rice varieties. Following an SDS-PAGE screen of rice germplasm from Taihu Valley of China, Japonica selection W3660 is identified to be a novel mutant characterized with low glutelin content. For fine mapping the mutant gene for low glutelin content, F2 and F3 populations were derived from a cross between W3660 and Jingrennuo. SDS-PAGE analysis of the total endosperm protein showed that the low glutelin content trait was controlled by a single dominant nuclear gene. Genetic mapping, using SSRs, located this gene to chromosome 2, in the region between SSR2-001/SSR2-004 and RM1358. The dis- tances of the two markers to the target gene were 1.1 cM and 3.8 cM respectively. By semi-quantitative RT-PCR analysis, the transcripts of GluB4/GluB5 genes located within the region do not change. However, GluB5 gene located proximal to SSR2-001/SSR2-004 was specifically reduced. SSR profiles of seven Japonica varieties were compared with that of W3660 for loci in the relevant genetic region. The markers SSR2-004 and RM1358 were used for marker- assisted selection. The selection efficiencies of SSR2-004 and RM1358 were 96.8% and 92.7% respectively. This provides a standard starting point for the breeding of low glutelin content rice varieties in China. 展开更多
关键词 fine mapping low glutelin content marker-assisted selection mutant rice.
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Evaluation and Selection of High Biomass Rice (<i>Oryza sativa L.</i>) for Drought Tolerance 被引量:3
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作者 Aditi Kondhia Rodante Escleto Tabien Amir Ibrahim 《American Journal of Plant Sciences》 2015年第12期1962-1972,共11页
Biomass production is important in increasing yield not only for food but also for bio-fuel production that depends on high dry matter. Due to climate change, occurrence of drought may be prevalent and this affects bo... Biomass production is important in increasing yield not only for food but also for bio-fuel production that depends on high dry matter. Due to climate change, occurrence of drought may be prevalent and this affects both grain and biomass yields in crops including rice. The objectives of this study were to determine the performance of selected high biomass breeding rice lines to different levels of drought and use several drought tolerance indices to identify best genotypes that could be grown in unfavorable water stressed areas. A rainfed and flooded trial was conducted to evaluate 20 selected breeding lines for biomass production and ten entries from the same set were grown in the greenhouse at three different field capacities (FC, 50%, 75%, 100%). Most of the genotypes performed well under non-stressed conditions (flooded and 100% FC) but some genotypes performed well in water stressed condition. The plants had lower plant height, tiller plant-1, and total biomass at maturity under rainfed conditions and their flowering was delayed compared to flooded conditions. In the greenhouse, water stress slowed the rate of increase in height, and produced lower shoot and root weight, percent dry matter (% DM) and total biomass. However, drought enhanced the rate of tiller production. Two genotypes were found to more tolerant to drought stress and could be used for cultivation under water stress condition to get optimum biomass yields. These genotypes can be identified using drought tolerance indices, particularly stress tolerance index (STI), geometric mean productivity (GMP), mean productivity (MP) and harmonic mean (HARM), as these have a similar ability to separate drought sensitive and tolerant genotypes. Genetic and molecular analyses, and detailed characterization of these genotypes will help understand their inheritance pattern and the number of genes controlling the traits and determine specific leaves and root traits important in developing high biomass rice. 展开更多
关键词 HIGH BIOmasS RICE Water Stress selection Indices
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Mass Selection for Fast Growth in the Third Generation of the Orange Line of the Manila Clam Ruditapes philippinarum 被引量:1
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作者 LIANG Jian HUO Zhongming +2 位作者 GUO Yongjun LI Yongren YAN Xiwu 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第6期1481-1485,共5页
The Manila clam Ruditapes philippinarum is natively distributed along the Pacific coast of Asia,where it is one of the most important bivalve species for local fisheries.This species has been intentionally introduced ... The Manila clam Ruditapes philippinarum is natively distributed along the Pacific coast of Asia,where it is one of the most important bivalve species for local fisheries.This species has been intentionally introduced due to its high adaptability to various coastal environments and is currently widely cultivated in Europe and North America.We have initiated a selective breeding program to improve the growth rate of the Manila clam since 2007,and a full-sib family with orange shell color was selected.This family features high survival but slow growth.Thereafter,two generations of mass selection were conducted in this family by 10% upward selection for faster growth.In 2011,three types of lines were produced by selecting the breeder from the second-generation of selected lines.These lines are SS(subject to three generations of selection for growth in shell length),SC(selected for the second but not the third generation),and C(randomly sampled individuals from the national population).The genetic parameters of the shell length including hR^2(realized heritability),SR(selection response),and GG(genetic gain)were analyzed.Results showed that the shell length of the SS line was significantly larger than those of the SC and C lines at all developmental stages(P<0.05).For the larval stage,the values of hR^2,SR,and GG were 0.42,0.73,and 6.66,respectively.For the juvenile stage,the values of hR^2,SR,and GG were 0.40,0.69,21.76,respectively.For grow-out stage,the values of hR^2,SR,and GG were 0.48,0.83,and 18.22,respectively.The results of hR^2 indicated the good potential of the SS line in selective breeding.The level of GG improvement was encouraging and consistent with the previous expectations.No inbreeding depressions in the shell length were observed in the SS and SC lines at all sampling days.All of the results indicate that maintaining selection pressure in successive generations may be effective in the selective breeding program of this family. 展开更多
关键词 Ruditapes philippinarum mass selection realized HERITABILITY GENETIC gain INBREEDING DEPRESSION
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The road toward Cd-safe rice:From mass selection to marker-assisted selection and genetic manipulation 被引量:2
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作者 Liang Sun Yongjun Tan Caiyan Chen 《The Crop Journal》 SCIE CSCD 2023年第4期1059-1071,共13页
Rice is an important dietary source of the toxic mineral cadmium(Cd) for populations in which rice is the main staple food.When grown in agricultural soils that are contaminated with Cd,rice often accumulates excessiv... Rice is an important dietary source of the toxic mineral cadmium(Cd) for populations in which rice is the main staple food.When grown in agricultural soils that are contaminated with Cd,rice often accumulates excessive Cd into the grains,which is a serious threat to agricultural sustainability and human health.To limit Cd accumulation in rice grains,studies on the genetic basis of Cd accumulation in rice have been carried out extensively,and some low-Cd rice varieties have also been developed in recent years.However,the challenges in low-Cd rice breeding still exist because the outcomes of the current genetic improvements for low-Cd rice cannot fully meet the requirements for the development of Cd-safe rice at present.In this review,we outline the progress in understanding the physiological mechanisms and the genetic nature of Cd accumulation in rice and summarize the strategies and outcomes of low-Cd rice breeding over the past decade.By graphing the physiological mechanism of Cd transport in the rice plant,three key steps and some underlying genes are summarized and discussed.Also,two genetic features of the natural variation in rice grain-Cd accumulation,the phenotypic plasticity and subspecies divergence,and the potential genetic explanations for these features are also discussed.Finally,we summarize and discuss current progress and the potential issues in low-Cd rice breeding using different breeding strategies.We hope to propose strategies for future success in the breeding of low-Cd rice varieties over the next decade. 展开更多
关键词 RICE Cadmium-safe Cadmium-free Gene manipulation mas
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Selection of superior families of Pinus massoniana in southern China for large-diameter construction timber 被引量:5
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作者 Zhangqi Yang Hui Xia +2 位作者 Jianhui Tan Yuanheng Feng Yongli Huang 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第2期475-484,共10页
This study addresses the increasing demand for large-diameter production timber,and considers the time and space variability of half-sib families of Pinus massoniana.Height,diameter at breast height(DBH)and timber vol... This study addresses the increasing demand for large-diameter production timber,and considers the time and space variability of half-sib families of Pinus massoniana.Height,diameter at breast height(DBH)and timber volume of 440 open-pollinated half-sib progeny families were investigated in 14 progeny trials in different years and production regions.An evaluation of the genetic variation of all half-sib families was carried out during the sustainable rapid growth period and individual volumes were characterized as a major index.ANOVA analysis showed that there was considerable variance in the growth traits of most families in different years and on different sites.The variations caused by temporal and spatial changes of the mating system required three selection methods for analysis.The results show that there were differences among the heritabilities of different growth traits by different halfsib progenies.Average heritability values of height,DBH and volume were 0.33,0.34 and 0.36,respectively.Fortyfive superior families were selected in every progeny test,12 were selected in progeny trials by different years and five in different habitat progeny trials.Three superior families(Gui GC553A,Gui GC414A and Gui GC431A)were selected,although in different years and production regions.The genetic gains of timber volume of these selected r families ranged from 1.20 to 47.00%,which could provide a foundation for superior wood property selection and serve as material for seed improvement and extension in surrounding areas. 展开更多
关键词 Pinus massoniana Open-pollinated progeny Large-diameter timber Superior family selection Mating system
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Genetic Variation Assessed with Microsatellites in Mass Selection Lines of the Pacific Oyster (Crassostrea gigas) in China 被引量:3
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作者 WANG Xubo LI Qi +1 位作者 YU Hong KONG Lingfeng 《Journal of Ocean University of China》 SCIE CAS 2016年第6期1039-1045,共7页
Abstract Four successive mass selection lines of the Pacific oyster, Crassostrea gigas, selected for faster growth in breeding pro- grams in China were examined at ten polymorphic microsatellite loci to assess the lev... Abstract Four successive mass selection lines of the Pacific oyster, Crassostrea gigas, selected for faster growth in breeding pro- grams in China were examined at ten polymorphic microsatellite loci to assess the level of allelic diversity and estimate the effective population size. These data were compared with those of their base population. The results showed that the genetic variation of the four generations were maintained at high levels with an average allelic richness of 18.8-20.6, and a mean expected heterozygosity of 0.902-0.921. They were not reduced compared with those of their base population. Estimated effective population sizes based on temporal variances in microsatellite frequencies were smaller to that of sex ratio-corrected broodstock count estimates. Using a rela- tively large number ofbroodstock and keeping an equal sex ratio in the broodstock each generation may have contributed to retaining the original genetic diversity and maintaining relatively large effective population size. The results obtained in this study showed that the genetic variation was not affected greatly by mass selection progress and high genetic variation still existed in the mass selection lines, suggesting that there is still potential for increasing the gains in future generations of C. gigas. The present study provided im- portant information for future genetic improvement by selective breeding, and for the design of suitable management guidelines for genetic breeding of C. gigas. 展开更多
关键词 Pacific oyster genetic variation MICROSATELLITE mass selection line effective population size
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Joint User Scheduling and Antenna Selection in Distributed Massive MIMO Systems with Limited Backhaul Capacity 被引量:9
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作者 XU Guozhen LIU An +2 位作者 JIANG Wei XIANG Haige LUO Wu 《China Communications》 SCIE CSCD 2014年第5期17-30,共14页
Massive MIMO systems offer a high spatial resolution that can drastically increase the spectral and/or energy efficiency by employing a large number of antennas at the base station(BS).In a distributed massive MIMO sy... Massive MIMO systems offer a high spatial resolution that can drastically increase the spectral and/or energy efficiency by employing a large number of antennas at the base station(BS).In a distributed massive MIMO system,the capacity of fiber backhaul that links base station and remote radio heads is usually limited,which becomes a bottleneck for realizing the potential performance gain of both downlink and uplink.To solve this problem,we propose a joint antenna selection and user scheduling which is able to achieve a large portion of the potential gain provided by the massive MIMO array with only limited backhaul capacity.Three sub-optimal iterative algorithms with the objective of sumrate maximization are proposed for the joint optimization of antenna selection and user scheduling,either based on greedy fashion or Frobenius-norm criteria.Convergence and complexity analysis are presented for the algorithms.The provided Monte Carlo simulations show that,one of our algorithms achieves a good tradeoff between complexity and performance and thus is especially fit for massive MIMO systems. 展开更多
关键词 massive MIMO limited backhaul capacity antenna selection user scheduling
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耐力运动通过激活Mas/PKA/CREB/UCP2信号通路减轻大鼠脑缺血/再灌注损伤
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作者 吴会生 吴华勋 +2 位作者 代文龙 程俊 郭培培 《中国药理学通报》 北大核心 2025年第6期1079-1085,共7页
目的观察耐力运动(endurance exercise,EE)对脑缺血/再灌注损伤(cerebral ischemia/reperfusion injury,CI/RI)大鼠的影响,并探讨其与Mas信号通路的关系。方法将成年的雄性SD大鼠72只随机分为4组(n=18):假手术组(Sham组)、脑缺血模型组(... 目的观察耐力运动(endurance exercise,EE)对脑缺血/再灌注损伤(cerebral ischemia/reperfusion injury,CI/RI)大鼠的影响,并探讨其与Mas信号通路的关系。方法将成年的雄性SD大鼠72只随机分为4组(n=18):假手术组(Sham组)、脑缺血模型组(Model组)、EE组(E组)和Mas受体拮抗剂A779预处理组(A组)。采用大脑中动脉阻断法建立CI/RI模型。E组和A组大鼠在模型制备前均规律跑步4周,A组还在模型制备前30 min注射A779。再灌注3 d后,通过神经功能缺陷评分(NDS)和Morris水迷宫评价大鼠认知功能。静脉注射伊文思蓝(EB)1 h后处死大鼠,取脑组织,测脑梗死体积、EB含量、ROS含量和海马CA1区的坏死率,Western blot检测大鼠的Mas信号通路相关蛋白表达。结果与Model组比较,E组的学习记忆及神经功能损伤明显减轻(P<0.05),脑梗死体积和缺血侧海马CA1区神经坏死程度均明显降低(P<0.05),ROS含量和脑组织EB含量均明显下降(P<0.05),Mas/PKA/CREB/UCP2信号通路相关蛋白表达明显增强(P<0.05);而Mas受体拮抗剂A779明显抑制上述效应(P<0.05)。结论EE可能是通过激活CI/RI大鼠的Mas/PKA/CREB/UCP2信号通路来抑制氧化应激程度,进而减轻大鼠CI/RI。 展开更多
关键词 耐力运动 鸢尾素 脑缺血 再灌注损伤 氧化应激 mas信号通路
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HOW TO MASTER THE DIFFERENTIATION OF SYNDROMES AND THE SELECTION OF ACUPOINTS QUICKLY
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作者 Zhuang JiaxiuInstitute of Acupuncture and Moxibustion, China Academy of TCM, Beijing 100700, China 《World Journal of Acupuncture-Moxibustion》 1994年第1期53-56,共4页
Differentiation of syndromes can be done by three steps:First to differentiate thenature of disease,second to differentiate the location of disease,third to analyse comprehensively thenature and location of disease.De... Differentiation of syndromes can be done by three steps:First to differentiate thenature of disease,second to differentiate the location of disease,third to analyse comprehensively thenature and location of disease.Depend on complete differentiation of syndromes,the acupoints are selected.Three cases are analysed to explain how to dominate preceding contents. 展开更多
关键词 DIFFERENTIATION of SYNDROMES selection of ACUPOINTS Nature of DISEASE Location of DISEASE
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Estimation of Crop Biomass Using GF-3 Polarization SAR Data Based on Genetic Algorithm Feature Selection 被引量:5
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作者 Kunpeng XU Lei ZHAO +3 位作者 Kun LI Erxue CHEN Wangfei ZHANG Hao YANG 《Journal of Geodesy and Geoinformation Science》 2020年第4期126-136,共11页
In recent years,Polarization SAR(PolSAR)has been widely used in the filed of crop biomass estimation.However,high dimensional features extracted from PolSAR data will lead to information redundancy which will result i... In recent years,Polarization SAR(PolSAR)has been widely used in the filed of crop biomass estimation.However,high dimensional features extracted from PolSAR data will lead to information redundancy which will result in low accuracy and poor transfer ability of the estimation model.Aiming at this problem,we proposed a estimation method of crop biomass based on automatic feature selection method using genetic algorithm(GA).Firstly,the backscattering coefficient,the polarization parameters and texture features were extracted from PolSAR data.Then,these features were automatically pre-selected by GA to obtain the optimal feature subset.Finally,based on this subset,a support vector regression machine(SVR)model was applied to estimate crop biomass.The proposed method was validated using the GaoFen-3(GF-3)QPSΙ(C-band,quad-polarization)SAR data.Based on wheat and rape biomass samples acquired from a synchronous field measurement campaign,the proposed method achieve relative high validation accuracy(over 80%)in both crop types.For further analyzing the improvement of proposed method,validation accuracies of biomass estimation models based on several different feature selection methods were compared.Compared with feature selection based on linear correlation,GA method has increased by 5.77%in wheat biomass estimation and 11.84%in rape biomass estimation.Compared with the method of recursive feature elimination(RFE)selection,the proposed method has improved crops biomass estimation accuracy by 3.90%and 5.21%,respectively. 展开更多
关键词 Polarization SAR estimation of crop biomass genetic algorithm feature selection GaoFen-3
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Responses to two-way selection on growth in mass-spawned F_1 progeny of Argopecten irradians concentricus(Say)
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作者 王辉 刘进 +2 位作者 李艳红 朱晓闻 刘志刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第2期349-357,共9页
In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop (Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program c... In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop (Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program currently being carried out in Beibu Bay in the South China Sea. A total of 146 adult scallops were randomly selected from the same cultured population ofA. i. concentricus, and divided into two groups in shell length (anterior-posterior measurement): large (4.91-6.02 cm, n=74) and small (3.31-4.18 cm, n=72). At the same time, a control group was also randomly sampled (4.21-4.88 cm, n=80). Mass-spawned F1 progenies from the three size groups were obtained and reared under identical conditions at all growth phases. The effects of two-way (or upward-downward) selection on fertilization rate, hatching rate, survival rate, daily growth in shell length and body weight were assessed in the three size groups. Results show that significant differences (P〈0.01) were found in hatching rate, survival rate and daily growth of F~ progenies, but not in fertilization rate (P〉0.05), among the three groups. The hatching rate, survival rate and daily growth of the progeny of large-sized parents were greater than those of the control group (P〈0.05), which in turn were larger than those of small-sized group (P〈0.05). Responses to selection by shell length and body weight were 0.32±0.04 cm and 2.18±0.05 g, respectively, for the upward selection, and -0.14±0.03 cm and -2.77±0.06 g, respectively, for the downward selection. The realized heritability estimates of shell length and body weight were 0.38±0.06 cm and 0.22±0.07 g for the upward selection, and 0.24±0.06 cm and 0.37±0.09 g for the downward selection, respectively. The change in growth by bidirectional selection suggests that high genetic variation may be present in the cultured bay scallop population in China. 展开更多
关键词 Argopecten irradians concentricus (Say) two-way selection response to selection realized heritability F1 progeny mass-spawned
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武威汉简瘀方对Ang Ⅱ诱导损伤的肾小球足细胞ACE2/Ang(1-7)/Mas受体轴的影响
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作者 寇雨顺 黎永祥 +3 位作者 李梦瑶 王鸿 沈路凡 伊琳 《时珍国医国药》 北大核心 2025年第8期1422-1427,共6页
目的研究武威汉简瘀方对经AngⅡ诱导损伤的肾小球足细胞(MPC)中ACE2/Ang(1-7)/Mas受体轴表达的影响,探讨武威汉简瘀方对高血压肾损伤的保护作用机制。方法将8周龄雌性SD大鼠30只随机分为模型组、缬沙坦组和武威汉简瘀方组,每组10只,灌胃... 目的研究武威汉简瘀方对经AngⅡ诱导损伤的肾小球足细胞(MPC)中ACE2/Ang(1-7)/Mas受体轴表达的影响,探讨武威汉简瘀方对高血压肾损伤的保护作用机制。方法将8周龄雌性SD大鼠30只随机分为模型组、缬沙坦组和武威汉简瘀方组,每组10只,灌胃1周后腹主动脉采血,离心收取血清并过滤,置于-80℃储存。将含药血清调整为低、中、高剂量,与模型组和缬沙坦组血清分别干预AngⅡ诱导损伤的肾小球足细胞模型。应用CCK-8法检测武威汉简瘀方对MPC增殖的影响;通过ELISA法检测Ang(1-7)表达;qRT-PCR检测ACE2和Mas表达;Western blot检测ACE2蛋白表达。结果CCK-8结果显示:缬沙坦组和瘀方低、中、高剂量组细胞活性均显著高于模型组(P<0.05)。ELISA结果显示:与模型组相比,缬沙坦组和低、中、高剂量组Ang(1-7)表达量均上调(P<0.05)。qRT-PCR结果显示:与模型组相比,缬沙坦组和中药方低、中、高剂量组ACE2和Mas表达量均上调(P<0.05)。Western blot结果显示:与模型组相比,缬沙坦组和中药方低、中、高剂量组ACE2蛋白表达量均上调(P<0.05)。结论武威汉简瘀方可能是通过调节ACE2/Ang(1-7)/Mas信号通路实现对肾功能的保护作用且有一定程度的浓度依赖性。 展开更多
关键词 武威汉简瘀方 高血压肾损伤 高血压 ACE2/Ang(1-7)/mas
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The research on rule of Acupoints and Massage Manipulations selection for Post-ischemic Stroke Constipation based on association rule and entropy clustering analysis 被引量:1
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作者 Long Zhang Xiao-Lin Zhang +3 位作者 A-Ru Sun Di Cao Zheng-Ri Cong Ming-Jun Liu 《Medical Data Mining》 2021年第4期8-20,共13页
Constipation is a common complication of stroke,and it is increasing year by year,which is worthy of attention.In fact,as an effective treatment for Post-ischemic Stroke Constipation,massage has been recognized by doc... Constipation is a common complication of stroke,and it is increasing year by year,which is worthy of attention.In fact,as an effective treatment for Post-ischemic Stroke Constipation,massage has been recognized by doctors at home and abroad.However,In the known research reports,massage prescriptions are complicated,therefore,a simple and effective massage prescription is urgently needed to effectively guide the clinic and promote it.In this study,we used association rule and entropy clustering analysis methods to mine clinical literature on Post-ischemic Stroke Constipation in 7 databases,and combined with data analysis,traditional chinese massage theory and clinical practice,a core new prescription is summarized.The core new prescription of massage in treating Post-ischemic Stroke Constipation take tonifying spleen,nourishing Qi and generating Body Fluid,promoting Qi,invigorating the circulation of blood and eliminating phlegm as the principle of treatment,which is accord with the pathogenesis of this disease,can better guide the clinical practice and facilitate the popularization and application of massage therapy. 展开更多
关键词 Stroke CONSTIPATION Association rule Entropy clustering masSAGE Rule of acupoint selection
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Impedance Matching Algorithm for Selection of Suitable Explosives for Any Rock Mass-A Case Study
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作者 Ajay Kumar Jha 《Journal of Geological Resource and Engineering》 2020年第2期55-65,共11页
Proper selection of the explosive is an important part of blast design.The judicious selection of explosives is governed by economic considerations and site/field conditions.The mine management desires to select an ex... Proper selection of the explosive is an important part of blast design.The judicious selection of explosives is governed by economic considerations and site/field conditions.The mine management desires to select an explosive that will give the lowest cost per unit of rock broken,while assuring that fragmentation,fragment size distribution,muck pile profile,muck pile diggability,displacement of the rock,onset of movement,face movement,burden relief rate,ground vibration and noise remains within control limits.Factors which influence the selection of an explosive include explosive cost,charge diameter,cost of drilling,fragmentation difficulties and fragment size requirement with loose muck pile condition,water conditions,atmospheric temperature,propagating ground,storage considerations,sensitivity considerations,explosive atmospheres and nearness of communities from mine.All these concerns can be handled effectively by using the impedance matching technology where explosive impedance is matched with rock impedance for optimal blast performance with due concern to productivity,economics and environment.This paper discusses a case study in limestone mines where rock impedance was determined by carrying out surface refraction test and a patented algorithm was used to estimate the explosives’properties i.e.VOD(velocity of detonation)and density of explosives required. 展开更多
关键词 Explosive selection impedance matching rock impedance explosive impedance
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Effects of feature selection and normalization on network intrusion detection 被引量:3
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作者 Mubarak Albarka Umar Zhanfang Chen +1 位作者 Khaled Shuaib Yan Liu 《Data Science and Management》 2025年第1期23-39,共17页
The rapid rise of cyberattacks and the gradual failure of traditional defense systems and approaches led to using artificial intelligence(AI)techniques(such as machine learning(ML)and deep learning(DL))to build more e... The rapid rise of cyberattacks and the gradual failure of traditional defense systems and approaches led to using artificial intelligence(AI)techniques(such as machine learning(ML)and deep learning(DL))to build more efficient and reliable intrusion detection systems(IDSs).However,the advent of larger IDS datasets has negatively impacted the performance and computational complexity of AI-based IDSs.Many researchers used data preprocessing techniques such as feature selection and normalization to overcome such issues.While most of these researchers reported the success of these preprocessing techniques on a shallow level,very few studies have been performed on their effects on a wider scale.Furthermore,the performance of an IDS model is subject to not only the utilized preprocessing techniques but also the dataset and the ML/DL algorithm used,which most of the existing studies give little emphasis on.Thus,this study provides an in-depth analysis of feature selection and normalization effects on IDS models built using three IDS datasets:NSL-KDD,UNSW-NB15,and CSE–CIC–IDS2018,and various AI algorithms.A wrapper-based approach,which tends to give superior performance,and min-max normalization methods were used for feature selection and normalization,respectively.Numerous IDS models were implemented using the full and feature-selected copies of the datasets with and without normalization.The models were evaluated using popular evaluation metrics in IDS modeling,intra-and inter-model comparisons were performed between models and with state-of-the-art works.Random forest(RF)models performed better on NSL-KDD and UNSW-NB15 datasets with accuracies of 99.86%and 96.01%,respectively,whereas artificial neural network(ANN)achieved the best accuracy of 95.43%on the CSE–CIC–IDS2018 dataset.The RF models also achieved an excellent performance compared to recent works.The results show that normalization and feature selection positively affect IDS modeling.Furthermore,while feature selection benefits simpler algorithms(such as RF),normalization is more useful for complex algorithms like ANNs and deep neural networks(DNNs),and algorithms such as Naive Bayes are unsuitable for IDS modeling.The study also found that the UNSW-NB15 and CSE–CIC–IDS2018 datasets are more complex and more suitable for building and evaluating modern-day IDS than the NSL-KDD dataset.Our findings suggest that prioritizing robust algorithms like RF,alongside complex models such as ANN and DNN,can significantly enhance IDS performance.These insights provide valuable guidance for managers to develop more effective security measures by focusing on high detection rates and low false alert rates. 展开更多
关键词 CYBERSECURITY Intrusion detection system Machine learning Deep learning Feature selection NORMALIZATION
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