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QTL Identification of the Insensitive Response to Photoperiod and Temperature in Soybean by Association Mapping 被引量:6
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作者 ZUO Qiao-mei WEN Zi-xiang +4 位作者 ZHANG Shu-yun HOU Jin-feng GAI Jun-yi YU De-yue XING Han 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1423-1430,共8页
The insensitive response to photoperiod and temperature is an important quantitative trait for soybean in wide adaptation breeding. The natural variation in response to photoperiod and temperature was detected using 2... The insensitive response to photoperiod and temperature is an important quantitative trait for soybean in wide adaptation breeding. The natural variation in response to photoperiod and temperature was detected using 275 accessions of soybean [Glycine max (L.) Merrill] from China. Genome-wide association mapping, based on population structure analysis, was carried out using 118 SSR markers by the TASSEL GLM (general linear model) program. Nine SSR markers (P〈0.01) were associated with the value of the response to photoperiod and temperature (VRPT) caused by days to flowering (DF), among which, Satt308 (LG M), Sattl50 (LG M) and Satt440 (LG l), were identified in both 2006 and 2007. Twelve SSR markers (P〈0.01) were associated with VRPT caused by days to maturity (DM), among which three markers, Satt387 (LG N), Satt307 (LG C2) and AW310961 (LG J), were detected in both 2006 and 2007. In addition, a total of 20 elite alleles were screened out over 2006 and 2007 for being associated with an insensitive response to photoperiod and temperature (IRPT) caused by DF and a total of seven different elite alleles were screened out for being associated with IRPT caused by DM. Among these elite alleles, five alleles, Satt150-244, Satt308-164, Satt308-206, Satt440-176, and Satt440-206, were associated with IRPT caused by DF and were identified in both years, but only one allele, Satt307-170, was identified as being associated with an IRPT caused by DM. Based on these elite alleles, a set of typical accessions were screened out. The result about the genetic basis of IRPT is meaningful for soybean wide adaption breeding. 展开更多
关键词 QTL association mapping SOYBEAN insensitive response photoperiod and temperature
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Prepulse inhibition (PPI) of tactile startle response in recombinant congenic strains of mice:QTL mapping and comparison with acoustic PPI
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作者 Adam Torkamanzehi Patricia Boksa Ridha Joober 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第3期139-151,共13页
Prepulse inhibition (PPI) of the startle response is a psychophysiological measure of sensorimotor gating believed to be cross-modal between different sensory systems. We analyzed the tactile startle response (TSR... Prepulse inhibition (PPI) of the startle response is a psychophysiological measure of sensorimotor gating believed to be cross-modal between different sensory systems. We analyzed the tactile startle response (TSR) and PPI of TSR (tPPI), using light as a prepulse stimulus, in the mouse strains A/J and C57BL/6J and 36 recombinant congenic strains derived from them. Parental strains were significantly different for TSR, but were comparable for tPPI. Among the congenic strains, variation for TSR was significant in both genetic backgrounds, but that of tPPI was significant only for the C57BL/6J background. Provisional mapping for loci modulating TSR and tPPI was carried out. Using mapping data from our previous study on acoustic startle responses (ASR) and PPI of ASR (aPPI), no common markers for aPPI and tPPI were identified. However, some markers were significantly associated with both ASR and TSR, at least in one genetic background. These results indicate cross-modal genetic regulation for the startle response but not for PPI, in these mouse strains. 展开更多
关键词 tactile startle response prepulse inhibition (PPI) acoustic startle response recombinant congenic strains of mice QTL mapping microsatellite markers
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Stochastic response analysis of noisy system with non-negative real-power restoring force by generalized cell mapping method
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作者 Qun HAN Wei XU Xiaole YUE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第3期329-336,共8页
The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping (GCM) method compute the transient and stationary probability density functions (PDFs) real... The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping (GCM) method compute the transient and stationary probability density functions (PDFs) real-power is used to Combined with the global properties of the noise-free system, the evolutionary process of the tran- sient PDFs is revealed. The results show that stochastic P-bifurcation occurs when the system parameter varies in the response analysis and the stationary PDF evolves from bimodal to unimodal along the unstable manifold during the bifurcation. 展开更多
关键词 stochastic response probability density function (PDF) generalized cell mapping (GCM) method real-power restoring force bifurcation
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Access to emergency medical services in Beijing:integrating web mapping application programming interfaces and empirical Bayesian Kriging interpolation analysis
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作者 Haolin Zhu Mo Xu +2 位作者 Luying Zhu Sijia Tian Jinjun Zhang 《World Journal of Emergency Medicine》 2025年第3期266-268,共3页
Emergency medical services (EMS) are a vital element of the public healthcare system in China,^([1])providing an opportunity to respond to critical medical conditions and save people’s lives.^([2])The accessibility o... Emergency medical services (EMS) are a vital element of the public healthcare system in China,^([1])providing an opportunity to respond to critical medical conditions and save people’s lives.^([2])The accessibility of EMS has received considerable attention in health and transport geography studies.^([3])One of the optimal gauges for evaluating the accessibility of EMS is the response time,which is defined as the time from receiving an emergency call to the arrival of an ambulance.^([4])Beijing has already reduced the response time to approximately12 min,and the next goal is to ensure that the response time across Beijing does not exceed 12 min (the information comes from the Beijing Emergency Medical Center). 展开更多
关键词 emergency medical services public healthcare system web mapping application programming interfaces empirical bayesian kriging interpolation analysis ACCESSIBILITY respond critical medical conditions response time
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基于ADO.NET的O/R Mapping中间件的研究 被引量:5
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作者 王丽芳 蒋泽军 +1 位作者 庄亮 曾杰 《西北工业大学学报》 EI CAS CSCD 北大核心 2006年第6期759-762,共4页
目前大多数软件开发都采用面向对象技术,而数据仍然保存在关系数据库中。由于对象模型和关系模型存在阻抗不匹配,因此实现对象与关系的映射已成为软件开发领域的关键问题。采用O/R M app ing(对象/关系映射)技术、XM L技术和软件分层的... 目前大多数软件开发都采用面向对象技术,而数据仍然保存在关系数据库中。由于对象模型和关系模型存在阻抗不匹配,因此实现对象与关系的映射已成为软件开发领域的关键问题。采用O/R M app ing(对象/关系映射)技术、XM L技术和软件分层的设计思想,实现了一个有效的数据库访问中间件,解决了利用ADO.NET开发应用程序遇到的数据表示和存取问题。 展开更多
关键词 数据库访问 阻抗失谐 中间件 对象关系映射 ADO.NET
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Simultaneous Localization and Mapping System Based on Labels 被引量:1
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作者 Tong Liu Panpan Liu +1 位作者 Songtian Shang Yi Yang 《Journal of Beijing Institute of Technology》 EI CAS 2017年第4期534-541,共8页
In this paper a label-based simultaneous localization and mapping( SLAM) system is proposed to provide localization to indoor autonomous robots. In the system quick response( QR) codes encoded with serial numbers ... In this paper a label-based simultaneous localization and mapping( SLAM) system is proposed to provide localization to indoor autonomous robots. In the system quick response( QR) codes encoded with serial numbers are utilized as labels. These labels are captured by two webcams,then the distances and angles between the labels and webcams are computed. Motion estimated from the two rear wheel encoders is adjusted by observing QR codes. Our system uses the extended Kalman filter( EKF) for the back-end state estimation. The number of deployed labels controls the state estimation dimension. The label-based EKF-SLAM system eliminates complicated processes,such as data association and loop closure detection in traditional feature-based visual SLAM systems. Our experiments include software-simulation and robot-platform test in a real environment. Results demonstrate that the system has the capability of correcting accumulated errors of dead reckoning and therefore has the advantage of superior precision. 展开更多
关键词 simultaneous localization and mapping (SLAM) extended Kalman filter (EKF) quick response (QR) codes artificial landmarks
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Dynamic Analysis of Stochastic Friction Systems Using the Generalized Cell Mapping Method 被引量:1
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作者 Shichao Ma Xin Ning Liang Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第1期49-59,共11页
Friction systems are a kind of typical non-linear dynamical systems in the actual engineering and often generate abundant dynamics phenomena.Because of non-smooth characteristics,it is difficult to handle these system... Friction systems are a kind of typical non-linear dynamical systems in the actual engineering and often generate abundant dynamics phenomena.Because of non-smooth characteristics,it is difficult to handle these systems by conventional analysis methods directly.At the same time,random perturbation often affects friction systems and makes these systems more complicated.In this context,we investigate the steady-state stochastic responses and stochastic P-bifurcation of friction systems under random excitations in this paper.And in order to retain the non-smooth of friction system,the generalized cell mapping(GCM)method is first used to the original stochastic friction systems without any approximate transformation.To verify the accuracy and validate the applicability of the suggested approach,we present two classical nonlinear friction systems,i.e.,Coulomb force model and Dahl force model as examples.Meanwhile,this method is in good agreement with the Monte Carlo simulation method and the computation time is greatly reduced.In addition,further discussion finds that the adjustable parameters can induce the stochastic P-bifurcation in the two examples,respectively.The stochastic P-bifurcation phenomena indicate that the stability of the friction system changes very sensitively with the parameters.Research of responses analysis and stochastic P-bifurcation has certain significances for the reliability and stability analysis of practical engineering. 展开更多
关键词 Friction systems NON-SMOOTH stochastic responses cell mapping
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Genetic analysis and QTL mapping of growth period traits and plant height traits in soybean recombinant inbred lines from Dongnong 47 × PI 317334-B
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作者 Jing Li Jiafan Sun +2 位作者 Minmin Li Xue Zhao Lin Zhao 《Oil Crop Science》 CSCD 2021年第2期66-73,共8页
High and stable yield is the main goal of soybean genetic improvement.In this study,association analysis was used to detect the quantitative trait loci(QTL)for the plant height,and soybean growth period using 182 SSR ... High and stable yield is the main goal of soybean genetic improvement.In this study,association analysis was used to detect the quantitative trait loci(QTL)for the plant height,and soybean growth period using 182 SSR markers in the RIL population of 136 F_(4:8) lines,which developed from a cross between photoperiod-insensitive cultivar‘Dongnong 47’and photoperiod-sensitive variety PI317334–B.The results showed that 33 QTLs related to soybean growth period and plant height traits were detected by compound interval mapping,and were located on 12 linkage groups including N,C1,C2,J,D1a,B2,E,G,A2,O,L,I,with the contribution rate of 7.85–33.84%.These QTL loci and linkage markers related to soybean photoperiod sensitivity,would be helpful to identify key genes that control soybean photoperiod sensitivity,and provide an important basis for the breeding of new photoperiod-insensitive soybean varieties based on molecular design breeding. 展开更多
关键词 SOYBEAN Photoperiod response Recombinant inbred lines SSR markers QTL genetic map
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Mapping of Defense Response Gene Homologs and Their Association with Resistance Loci in Maize
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作者 Gui-Xiang Wang Yu Chen +6 位作者 Jiu-Ran Zhao Lin Li Schuyler S. Korban Feng-Ge Wang Jian-Sheng Li Jin-Rui Dai Ming-Liang Xu 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2007年第11期1580-1598,共19页
Defense response genes in higher plant species are involved in a variety of signal transduction pathways and biochemical reactions to counterattack invading pathogens. In this study, a total of 366 non-redundant defen... Defense response genes in higher plant species are involved in a variety of signal transduction pathways and biochemical reactions to counterattack invading pathogens. In this study, a total of 366 non-redundant defense response gene homologs (DRHs), including 124 unigenes/expressed sequence tags, 226 tentative consensuses, and 16 DRH contigs have been identified by mining the Maize Genetics and Genomics and The Institute for Genomic Research maize databases using 35 essential defense response genes. Of 366 DRHs, 202 are mapped to 152 loci across ten maize chromosomes via both the genetic and in silico mapping approaches. The mapped DRHs seem to cluster together rather than be evenly distributed along the maize genome. Approximately half of these DHRs are located in regions harboring either major resistance genes or quantitative trait loci (QTL). Therefore, this comprehensive DRH linkage map will provide reference sequences to identify either positional candidate genes for resistance genes and/or QTLs or to develop makers for fine-mapping and marker-assisted selection of resistance genes and/or QTLs. 展开更多
关键词 defense response gene disease resistance MAIZE molecular mapping.
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Extreme gradient boosting with Shapley Additive Explanations for landslide susceptibility at slope unit and hydrological response unit scales
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作者 Ananta Man Singh Pradhan Pramit Ghimire +3 位作者 Suchita Shrestha Ji-Sung Lee Jung-Hyun Lee Hyuck-Jin Park 《Geoscience Frontiers》 2025年第4期357-372,共16页
This study provides an in-depth comparative evaluation of landslide susceptibility using two distinct spatial units:and slope units(SUs)and hydrological response units(HRUs),within Goesan County,South Korea.Leveraging... This study provides an in-depth comparative evaluation of landslide susceptibility using two distinct spatial units:and slope units(SUs)and hydrological response units(HRUs),within Goesan County,South Korea.Leveraging the capabilities of the extreme gradient boosting(XGB)algorithm combined with Shapley Additive Explanations(SHAP),this work assesses the precision and clarity with which each unit predicts areas vulnerable to landslides.SUs focus on the geomorphological features like ridges and valleys,focusing on slope stability and landslide triggers.Conversely,HRUs are established based on a variety of hydrological factors,including land cover,soil type and slope gradients,to encapsulate the dynamic water processes of the region.The methodological framework includes the systematic gathering,preparation and analysis of data,ranging from historical landslide occurrences to topographical and environmental variables like elevation,slope angle and land curvature etc.The XGB algorithm used to construct the Landslide Susceptibility Model(LSM)was combined with SHAP for model interpretation and the results were evaluated using Random Cross-validation(RCV)to ensure accuracy and reliability.To ensure optimal model performance,the XGB algorithm’s hyperparameters were tuned using Differential Evolution,considering multicollinearity-free variables.The results show that SU and HRU are effective for LSM,but their effectiveness varies depending on landscape characteristics.The XGB algorithm demonstrates strong predictive power and SHAP enhances model transparency of the influential variables involved.This work underscores the importance of selecting appropriate assessment units tailored to specific landscape characteristics for accurate LSM.The integration of advanced machine learning techniques with interpretative tools offers a robust framework for landslide susceptibility assessment,improving both predictive capabilities and model interpretability.Future research should integrate broader data sets and explore hybrid analytical models to strengthen the generalizability of these findings across varied geographical settings. 展开更多
关键词 Landslide susceptibility mapping Hydrological response units Slope units Extreme gradient boosting Hyper parameter tuning Shapley additive explanations
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Evaluation of 30 DNA damage response and 6 mismatch repair gene mutations as biomarkers for immunotherapy outcomes across multiple solid tumor types 被引量:2
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作者 Zhe Gong Yue Yang +1 位作者 Jieyun Zhang Weijian Guo 《Cancer Biology & Medicine》 SCIE CAS CSCD 2021年第4期1080-1091,共12页
Objective:DNA damage response(DDR)genes have low mutation rates,which may restrict their clinical applications in predicting the outcomes of immune checkpoint inhibitor(ICI)treatment.Thus,a systemic analysis of multip... Objective:DNA damage response(DDR)genes have low mutation rates,which may restrict their clinical applications in predicting the outcomes of immune checkpoint inhibitor(ICI)treatment.Thus,a systemic analysis of multiple DDR genes is needed to identify potential biomarkers of ICI efficacy.Methods:A total of 39,631 patients with mutation data were selected from the cBioPortal database.A total of 155 patients with mutation data were obtained from the Fudan University Shanghai Cancer Center(FUSCC).A total of 1,660 patients from the MSK-IMPACT cohort who underwent ICI treatment were selected for survival analysis.A total of 249 patients who underwent ICI treatment from the Dana-Farber Cancer Institute(DFCI)cohort were obtained from a published dataset.The Cancer Genome Atlas(TCGA)level 3 RNA-Seq version 2 RSEM data for gastric cancer were downloaded from cBioPortal.Results:Six MMR and 30 DDR genes were included in this study.Six MMR and 20 DDR gene mutations were found to predict the therapeutic efficacy of ICI,and most of them predicted the therapeutic efficacy of ICI,in a manner dependent on TMB,except for 4 combined DDR gene mutations,which were associated with the therapeutic efficacy of ICI independently of the TMB.Single MMR/DDR genes showed low mutation rates;however,the mutation rate of all the MMR/DDR genes associated with the therapeutic efficacy of ICI was relatively high,reaching 10%–30%in several cancer types.Conclusions:Coanalysis of multiple MMR/DDR mutations aids in selecting patients who are potential candidates for immunotherapy. 展开更多
关键词 Immune checkpoint inhibitor therapy prediction of efficacy tumor mutation burden mismatch repair deficiency DNA damage response genes
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Mismatch repair protein expression and intratumoral budding in rectal cancer are associated with an increased pathological complete response to preoperative chemoradiotherapy: A case-control study
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作者 Leonardo S Lino-Silva Armando Gamboa-Domínguez +3 位作者 Diego Zú?iga-Tamayo Rosa A Salcedo-Hernández Lucely Cetina David Cantú-de-León 《World Journal of Clinical Oncology》 CAS 2018年第7期133-139,共7页
AIM To determine whether the association of rectal adenocarcinoma with a defective-mismatch repair system(dMMR) was associated with a pathological complete response(pCR) to preoperative chemoradiotherapy.METHODS A cas... AIM To determine whether the association of rectal adenocarcinoma with a defective-mismatch repair system(dMMR) was associated with a pathological complete response(pCR) to preoperative chemoradiotherapy.METHODS A case-control study was designed with the aim of determining if patients with rectal adenocarcinoma with dM MR had an associated high pCR rate in response to neoadjuvant chemoradiotherapy(nCRT).RESULTS Seventy-two cases with pCR were compared against 144 controls without pCR. Across 216 cases, the mean age was 56.8 years, 140(64.8%) were men, and 63(29.2%) demonstrated the dMMR system. The pCR was associated with G1 tumors, dMMR, the absence of vascular invasion, and low tumor budding in the pretreatment biopsy. In a multivariant analysis, the factors associated with pCR were dMMR(OR: 2.61; 95%CI: 1.355-5.040, P = 0.004) and a low degree of tumor budding(OR: 2.52; 95%CI: 1.366-4.894, P = 0.025).CONCLUSION We found an independent association between dMMR and a low rate of tumor budding, with a higher rate of pCR, in the basal biopsies of patients with rectal carcinoma subjected to nCRT. 展开更多
关键词 RECTAL cancer CHEMORADIOTHERAPY Tumor BUDDING mismatch repair Pathological complete response
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基于思维导图的急救教学培训提升急诊科护士急救应对能力的效果研究
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作者 吕月 孙莹 赵诺 《临床研究》 2026年第2期195-198,共4页
目的探讨思维导图在急诊科护士急救知识培训中的应用价值,评价其对护士急救理论掌握、技能操作及急救综合能力的提升效果。方法采用类实验研究设计,便利选取2025年1月至2025年4月解放军总医院急诊科护士62名,便利抽样纳入后,采用随机数... 目的探讨思维导图在急诊科护士急救知识培训中的应用价值,评价其对护士急救理论掌握、技能操作及急救综合能力的提升效果。方法采用类实验研究设计,便利选取2025年1月至2025年4月解放军总医院急诊科护士62名,便利抽样纳入后,采用随机数字表法分为对照组(n=31,传统培训)和观察组(n=31,思维导图联合传统培训)。培训后比较两组理论考核成绩、技能操作评分、综合能力评分。结果培训后,观察组理论考核得分[(92.5±3.8)分]高于对照组[(84.2±5.1)分],差异有统计学意义(t=7.392,P<0.001)。观察组单人心肺复苏、除颤仪使用、简易呼吸器使用、呼吸机使用得分均高于对照组,差异有统计学意义(P<0.05);两组静脉穿刺得分比较,差异无统计学意义(P>0.05)。观察组实操对应知识、评估与判断能力、沟通技巧、团队配合能力得分均高于对照组,差异有统计学意义(P<0.05)。结论思维导图辅助急救知识培训,除静脉穿刺外,可显著提升急诊科护士的急救知识及综合急救能力,优化团队协作效率。 展开更多
关键词 思维导图 急救知识培训 急诊科护士 应急能力 情景模拟
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Identification of prior candidate genes for Sclerotinia local resistance in Brassica napus using Arabidopsis cDNA microarray and Brassica-Arabidopsis comparative mapping 被引量:2
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作者 LIU Renhu ZHAO Jianwei +1 位作者 XIAO Yong MENG Jinling 《Science China(Life Sciences)》 SCIE CAS 2005年第5期460-470,共11页
Arabidopsis cDNA arrays were used to screen the local-defense-associated genes in oilseed rape(Brassica napus L.)at the challenge of Sclerotinia sclerotiorum.61 genes with two-fold expression changes were screened out... Arabidopsis cDNA arrays were used to screen the local-defense-associated genes in oilseed rape(Brassica napus L.)at the challenge of Sclerotinia sclerotiorum.61 genes with two-fold expression changes were screened out from the local tissue around the necrosis.Among them,36 unique genes were up-regulated and 25 unique genes were down-regulated.RT-PCR and Northern blot results were consistent with the array results,suggesting Arabidopsis arrays were useful for transcriptional profiling of B.napus genes.Some of these genes were located in the interval of some QTLs for Sclerotinia resistance in B.napus by Brassica-Arabi-dopsis comparative mapping.These genes may have priority to be pursued for more intensive research. 展开更多
关键词 Sclerotinia sclerotiorum Brassica-Arabidopsis comparative mapping MICROARRAY defense response plant-patho-gen interaction
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Molecular cloning, expression analysis and chromosomal mapping of salt-responsive cDNAs in rice (Oryza sativa L.) 被引量:2
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作者 李子银 张劲松 陈受宜 《Science China(Life Sciences)》 SCIE CAS 1999年第5期506-516,共11页
By using differential display PCR (DD-PCR) technique, two salt-inducible and one salt-repressed cDNA fragments were isolated from rice. The three cDNA fragments were characterized respectively as partial sequence of r... By using differential display PCR (DD-PCR) technique, two salt-inducible and one salt-repressed cDNA fragments were isolated from rice. The three cDNA fragments were characterized respectively as partial sequence of rice S-adenosylmethionine decarboxylase (SAMDC) gene, a new member of translation elongation factor lA gene (named REF1A), and a novel gene whose function is unknown (named SRG1). The full-length cDNA of SAMDC gene (named SAMDC1) was further isolated by RT-PCR approach and the deduced polypeptide was found to be homologous to SAMDC proteins of other plants, yeast and human. Northern hybridization revealed that expression of SAMDC1 and REF1A was induced, while SRG1 was dramatically repressed, by salinity stress. Southern blot analysis demonstrated that SAMDC 1 and SRG1 were present as a single copy gene in rice genome, whereas rice REF1A gene was organized as a gene family. The REF1A, SAMDC1, and SRG1 genes were located on chromosome 3,4, and 6 respectively by RFLP mapping approach using ZYQ8/JX17 DH population and RFLP linkage maps. 展开更多
关键词 RICE ( Oryza SALIVA L.) salt-responsive gene DIFFERENTIAL display PCR DIFFERENTIAL expression chromosomal mapping.
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拟周期驱动Boussinesq方程响应解的存在性
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作者 杨莲 舒兴奎 王芬芬 《四川大学学报(自然科学版)》 北大核心 2026年第2期323-327,共5页
本文研究满足铰接边界条件的拟周期驱动Boussinesq方程{y_(tt)(t,x)=μy_(xxxxx)+y_(xx)+(y^(3))_(xx)+εf(ωt,x),x∈T=[0,π],y(t,0)=y(t,π)=y_(xx)(t,0)=y_(xx)(t,π)=0响应解的存在性,其中μ>1,f:T^(d)×T→R,T^(d)=(R\2πZ... 本文研究满足铰接边界条件的拟周期驱动Boussinesq方程{y_(tt)(t,x)=μy_(xxxxx)+y_(xx)+(y^(3))_(xx)+εf(ωt,x),x∈T=[0,π],y(t,0)=y(t,π)=y_(xx)(t,0)=y_(xx)(t,π)=0响应解的存在性,其中μ>1,f:T^(d)×T→R,T^(d)=(R\2πZ)^(d)是关于时间t的拟周期解析函数或拟周期高阶光滑函数,ω=(ω_(1),ω_(2),…,ω_(d))∈R^(d)\{0}有理无关,正整数d≥2,ε任意小。根据驱动项不同的光滑性,本文利用压缩映射原理相应得到了方程响应解的存在性。与已有结果相比,本文将频率维度从2维提升到有限维,同时降低了对驱动项光滑性的要求。 展开更多
关键词 BOUSSINESQ方程 响应解 压缩映射原理
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具有任意频率的拟周期驱动阻尼振子方程响应解的存在性
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作者 舒兴奎 杨莲 王芬芬 《山东大学学报(理学版)》 北大核心 2026年第2期99-105,共7页
致力于寻找一个具有任意频率的拟周期驱动阻尼振子方程x_(tt)+μx_(t)+x-βx^(2)=εf(ωt)响应解的存在性(即与驱动频率相同的拟周期解)。当μ≠0且远离零时,系统是双曲的(特征值的实部非零),此时不会出现小除数问题。因此,在不对频率... 致力于寻找一个具有任意频率的拟周期驱动阻尼振子方程x_(tt)+μx_(t)+x-βx^(2)=εf(ωt)响应解的存在性(即与驱动频率相同的拟周期解)。当μ≠0且远离零时,系统是双曲的(特征值的实部非零),此时不会出现小除数问题。因此,在不对频率ω施加任何算术性条件,也不要求驱动项的平均是零的情况下,将原方程响应解的存在性转化为Banach空间中不动点问题,分别在解析、高阶可微的情形下用压缩映射原理证明方程响应解的存在性。 展开更多
关键词 振子方程 响应解 压缩映射原理
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Slam Technology on Disaster Response
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作者 Zakari Tukur Ibrahim Junyi He 《World Journal of Engineering and Technology》 2024年第3期695-714,共20页
Disaster response demands rapid, accurate, and comprehensive situational awareness. This study explores the potential of Simultaneous Localization and Mapping (SLAM) technology to enhance disaster response efforts. By... Disaster response demands rapid, accurate, and comprehensive situational awareness. This study explores the potential of Simultaneous Localization and Mapping (SLAM) technology to enhance disaster response efforts. By integrating sensors and algorithms, SLAM enables autonomous systems to create detailed maps of disaster-stricken areas while simultaneously determining their own location. This research investigates the application of SLAM in various disaster scenarios, assesses its performance in challenging conditions, and analyzes its potential to improve search and rescue, damage assessment, and resource allocation. The findings highlight the advantages of SLAM in providing real-time data, supporting decision-making, and increasing the efficiency of disaster response operations. 展开更多
关键词 Autonomous Vehicles Disaster response SENSORS mapping SLAM
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基于双期CT扫描的参数效应图在慢性阻塞性肺疾病肺功能及自觉症状评估中的价值
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作者 方春 王音 管佳成 《临床肺科杂志》 2026年第1期14-18,共5页
目的探讨基于双期CT扫描的参数效应图(PRM)在慢性阻塞性肺疾病(慢阻肺)患者肺功能评估及自觉症状中的价值。方法前瞻性纳入2023年1月—2024年6月间在我院行深吸气与呼气双期CT扫描及肺功能测试(PFT)的94例慢阻肺患者,得到PRM参数[PRM^(E... 目的探讨基于双期CT扫描的参数效应图(PRM)在慢性阻塞性肺疾病(慢阻肺)患者肺功能评估及自觉症状中的价值。方法前瞻性纳入2023年1月—2024年6月间在我院行深吸气与呼气双期CT扫描及肺功能测试(PFT)的94例慢阻肺患者,得到PRM参数[PRM^(EMPH)(以百分比计算的肺气肿区);PRM^(fSAD)(功能性小气道病变所致空气潴留区);PRM^(NORM)(正常肺实质区)]、PFT参数[FEV_(1)(第1秒用力呼气量);FVC(用力肺活量);FEV_(1)/FVC、第1秒用力呼气量占预计值的百分比(FEV_(1)%pred)]及自觉症状评分(改良版英国医学研究委员会呼吸问卷,mMRC;慢阻肺患者自我评估测试,CAT),分别进行PRM参数与PFT参数及自觉症状评分的相关性分析。结果慢阻肺全球倡议(global initiative for chronic obstructive lung disease,GOLD)各级患者之间的PRM^(EMPH)、PRM^(fSAD)、PRM^(NORM)均有差别,PRM^(EMPH)随着GOLD分级增加而增加,GOLD 1-3级PRM^(fSAD)随着GOLD分级增加而增加,GOLD 4级因PRM^(EMPH)占比较高而PRM^(fSAD)轻微降低,同时PRM^(NORM)随着GOLD分级增加而降低。慢阻肺患者的PRM参数与FEV_(1)、FEV_(1)%pred相关性较好,其中PRM^(NORM)与FEV_(1)及FEV_(1)%pred之间的r值较高,分别为0.839(P<0.001)及0.885(P<0.001)。PRM^(EMPH)、PRM^(fSAD)、PRM^(NORM)与mMRC、CAT评分均有较好的相关性,其中PRM^(NORM)与mMRC、CAT评分之间的r值较高,为-0.790(P<0.001)、-0.814(P<0.001)。结论PRM参数与肺功能参数、患者自觉症状评分有较好的相关性,尤其PRM^(NORM)能较准确反映患者慢阻肺程度、肺功能和患者自觉症状,是评估肺功能和患者自觉症状非常有潜力的指标。 展开更多
关键词 慢性阻塞性肺疾病 计算机断层扫描 参数效应图
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基于DRU-HVDC送出系统的海上风电惯量支撑协调控制
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作者 黄宝龙 赵晋斌 +2 位作者 毛玲 潘超 边晓燕 《电力系统自动化》 北大核心 2026年第4期46-55,共10页
大规模海上风电场经二极管整流单元(DRU)的高压直流(HVDC)系统送出方案在经济技术方面具有显著优势。然而,深远海风电场因长距离通信设备成本以及通信延时的影响,难以及时获取受端电网频率变化信息并提供惯量支撑。因此,提出一种基于DR... 大规模海上风电场经二极管整流单元(DRU)的高压直流(HVDC)系统送出方案在经济技术方面具有显著优势。然而,深远海风电场因长距离通信设备成本以及通信延时的影响,难以及时获取受端电网频率变化信息并提供惯量支撑。因此,提出一种基于DRU换流站运行特性的快速低延时频率映射-还原方法,协调控制直流电容储能-风机转子动能参与惯量响应。首先,文中介绍了海上风电场经DRU-HVDC送出系统拓扑结构和稳态运行特性。然后,受端换流站采用虚拟惯量控制方式,将电网频率变化映射为直流电压变化,同时阐明DRU换流站运行时海上交流侧与直流侧电气量间耦合特性,风机仅需本地检测电压幅值和功率来还原电网频率信息,并依据还原后的频率信息依次协调控制释放直流电容能量-风机转子动能。最后,在PSCAD/EMTDC环境中搭建了海上风电场经DRU-HVDC送出系统的仿真模型,仿真结果验证了所提出的频率映射-还原方法和惯量响应协调控制方法的可行性,降低通信延时对系统惯量响应速度的影响,提升受端电网惯性水平。 展开更多
关键词 二极管整流单元 高压直流系统 海上风电场 频率映射-还原 储能 转子动能 惯量响应
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