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北京黑猪AQP9和RPS10基因多态性及其与背膘厚的关联分析
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作者 祝雪丽 张龙超 +2 位作者 王立贤 蒲蕾 刘欣 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第1期87-98,共12页
旨在研究水通道蛋白9(aquaporins9,AQP9)及核糖体蛋白10(ribosomal protein S10,RPS10)基因多态性及其与北京黑猪背膘厚的相关性,以期能够获得北京黑猪背膘厚的有效标记。本研究以413头北京黑猪为研究对象,测定不同部位(肩部、6-7肋间... 旨在研究水通道蛋白9(aquaporins9,AQP9)及核糖体蛋白10(ribosomal protein S10,RPS10)基因多态性及其与北京黑猪背膘厚的相关性,以期能够获得北京黑猪背膘厚的有效标记。本研究以413头北京黑猪为研究对象,测定不同部位(肩部、6-7肋间、胸腰结合、腰荐结合)的背膘厚度。PCR扩增AQP9和RPS10基因的启动子区和外显子区序列筛选SNP位点,并将SNPs与各部位背膘厚进行关联分析。运用荧光定量PCR检测基因的差异表达。结果发现,AQP9基因启动子区有4个突变位点,其中1个SNP:rs332699245 A>C与胸腰结合处背膘厚关联显著(P<0.05),且该位点突变预测到了结合转录因子的改变;RPS10基因在3′UTR、CDS区共有8个突变位点,其中5个与背膘厚显著关联:rs80795904 C>G、rs80932213 T>C与6~7肋间背膘厚关联显著(P<0.05),rs3469834461 C>T与肩部背膘厚、四点平均背膘厚关联显著(P<0.05),rs80862457 C>T与胸腰结合处背膘厚、腰荐结合处背膘厚关联显著(P<0.05),rs336938272 A>C与6~7肋间背膘厚、腰荐结合处背膘厚、四点平均背膘厚均关联显著(P<0.05);且在3′UTR区检测到1个SNP(rs80862457 C>T),位于小RNA(microRNA,miRNA)结合靶点。基因表达差异分析表明,rs332699245 A>C中AA型个体的AQP9基因mRNA水平显著高于AC型个体(P<0.05),rs80862457 C>T中TT型个体的RPS10基因mRNA水平显著高于CC型个体(P<0.05)。综上所述,AQP9和RPS10基因与北京黑猪背膘厚显著关联,rs332699245 A>C和rs80862457 C>T位点可作为北京黑猪背膘厚选育的潜在分子标记,为北京黑猪的选育提供理论支撑。 展开更多
关键词 北京黑猪 AQP9 rps 10 背膘厚度 关联分析
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3RPS并联机构的运动学误差建模及其分析 被引量:1
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作者 王瑞 彭高磊 +1 位作者 郭祥雨 钟诗胜 《机械设计与制造》 北大核心 2024年第2期189-192,197,共5页
为了提高XYZ-3RPS六轴卧式混联机床的运动学精度,建立了3RPS并联机构的运动学参数误差模型。首先对3RPS并联机构的几何误差源进行了分析。然后基于闭环矢量微分法建立了3RPS并联机构包含铰点位置误差、转动副轴线方向误差、驱动支链零... 为了提高XYZ-3RPS六轴卧式混联机床的运动学精度,建立了3RPS并联机构的运动学参数误差模型。首先对3RPS并联机构的几何误差源进行了分析。然后基于闭环矢量微分法建立了3RPS并联机构包含铰点位置误差、转动副轴线方向误差、驱动支链零位杆长误差等27项结构参数误差对末端位姿误差的映射模型。最后设计了仿真实验,利用ADAMS的虚拟样机技术,获取机构实际末端位姿误差。通过与误差模型的结果对比,验证了所分析的27项结构参数误差设定值在(0.1~0.2)mm的范围内,误差模型的位置误差求解精度大于0.01mm,姿态误差求解精度大于0.01°。进一步的数值验证表明,误差模型的精度会随着结构参数误差值的减小而显著提高,为3RPS等少自由度并联机构的误差建模和运动学标定提供理论依据。 展开更多
关键词 运动学精度 3rps并联机构 误差建模 ADAMS仿真验证
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RPS6亚基肽段抑制S180肿瘤细胞的分子机制
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作者 蒲帝宏 叶姿妤 +4 位作者 周丽倩 刘欣岚 鲁艳 侯怡铃 丁祥 《生物学杂志》 CAS CSCD 北大核心 2024年第2期32-38,共7页
为探究核糖体蛋白RPS6亚基肽段对S180肿瘤细胞基因表达的影响及抑制肿瘤细胞的关键分子和信号通路,以S180荷瘤小鼠为模型,用RPS6亚基肽段处理S180荷瘤小鼠,对S180肿瘤细胞进行Illumina测序获得差异表达的基因,并对这些差异基因进行GO和K... 为探究核糖体蛋白RPS6亚基肽段对S180肿瘤细胞基因表达的影响及抑制肿瘤细胞的关键分子和信号通路,以S180荷瘤小鼠为模型,用RPS6亚基肽段处理S180荷瘤小鼠,对S180肿瘤细胞进行Illumina测序获得差异表达的基因,并对这些差异基因进行GO和KEGG分析。基因表达结果显示,RPS6亚基肽段会导致mt-Cytb、mt-Nd1、Rpl13基因表达降低,阻碍S180肿瘤细胞的氧化磷酸化过程。GO分析结果显示,RPS6亚基肽段抑制肿瘤细胞关键门类集中于质膜和质膜外侧组成成分的变化及免疫反应调节和免疫细胞的激活。差异基因结果显示,RPS6亚基肽段通过增强PRL/PRLR信号,上调Uchl1基因表达,诱导肿瘤细胞周期停滞。KEGG通路富集分析结果显示,穿孔素(PRF1)和颗粒酶B(GZMB)表达诱导细胞凋亡,同时自然杀伤细胞(natural killer cell,NK)介导的细胞毒性与NF-κB信号通路信号增强,IFN-γ和TNF-α表达上调共同参与RPS6亚基肽段作用下的S180肿瘤细胞凋亡,抑制S180肿瘤细胞增殖。RPS6亚基肽段导致S180肿瘤细胞细胞周期停滞,并诱导自然杀伤细胞介导的细胞毒性及NF-κB信号通路的上调导致S180肿瘤细胞凋亡,为RPS6亚基肽段在抗肿瘤研究的应用提供一定的理论依据。 展开更多
关键词 核糖体蛋白rps6 小分子多肽 RNA-Seq测序 差异表达基因 NF-κB信号通路
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工程车辆3-RPS座椅悬架半主动滑模控制
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作者 樊书伟 燕碧娟 +1 位作者 叶伟 张文军 《噪声与振动控制》 CSCD 北大核心 2024年第3期158-164,共7页
工程车辆处于恶劣的工作环境中,垂向单维度的被动减振无法满足实际需求。为解决该问题,依据可实现三维减振的3-RPS并联机构座椅悬架,提出一种新型三维控制策略。基于“座椅-人体”三维振动数学模型,设计一种新的三维天棚控制模型,作为... 工程车辆处于恶劣的工作环境中,垂向单维度的被动减振无法满足实际需求。为解决该问题,依据可实现三维减振的3-RPS并联机构座椅悬架,提出一种新型三维控制策略。基于“座椅-人体”三维振动数学模型,设计一种新的三维天棚控制模型,作为滑模控制的参考对象。设计滑模控制器,并根据Lyapunov稳定判据,对控制系统的稳定性进行分析判断。利用Simulink软件建立座椅-人体受振模型,对处于E、F、G级3种路面环境中,分别采用滑模控制以及被动控制模式的座椅的减振效果进行仿真对比分析。结果表明,相较于被动控制的座椅悬架,采用三维滑模控制的座椅悬架在垂直方向上的加速度下降率在38.88%至57.06%之间;俯仰方向上的角加速度的下降率在36.00%至54.89%之间;侧倾方向上的角加速度的下降率在49.58%至59.97%之间。且可有效降低垂直方向上的加速度峰值,对于冲击载荷减振性能良好。研究成果可为半主动多维减振座椅悬架控制策略的研究提供一定参考。 展开更多
关键词 振动与波 工程车辆 3-rps并联机构 三维天棚控制 滑模控制
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Comparison study on measurement of rail weld joint between inertial reference method and multi-point chord reference method
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作者 Yifan Shi Yuan Wang +1 位作者 Xiaozhou Liu Ping Wang 《Railway Sciences》 2024年第1期69-83,共15页
Purpose – Straightness measurement of rail weld joint is of essential importance to railway maintenance. Dueto the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint ... Purpose – Straightness measurement of rail weld joint is of essential importance to railway maintenance. Dueto the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint with a5-m wavelength range, leaving a significant knowledge gap in this field.Design/methodology/approach – In this study, the authors used the well-established inertial referencemethod (IR-method), and the state-of-the-art multi-point chord reference method (MCR-method). Two methodshave been applied in different types of rail straightness measurement trollies, respectively. These instrumentswere tested in a high-speed rail section within a certain region of China. The test results were ultimatelyvalidated through using traditional straightedge and feeler gauge methods as reference data to evaluate the railweld joint straightness within the 5-m wavelength range.Findings – The research reveals that IR-method and MCR-method produce reasonably similar measurementresults for wavelengths below 1 m. However, MCR-method outperforms IR-method in terms of accuracy forwavelengths exceeding 3 m. Furthermore, it was observed that IR-method, while operating at a slower speed,carries the risk of derailing and is incapable of detecting rail weld joints and low joints within the track.Originality/value – The research compare two methods’ measurement effects in a longer wavelength rangeand demonstrate the superiority of MCR-method. 展开更多
关键词 Rail weld joint Inertial reference method Short-wavelength irregularities Multi-point chord reference method 5-m wavelength range
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Pathological and Etiological Aspects of Nephrotic Syndrome at the Niamey General Reference Hospital
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作者 Djibrilla Gani Salamatou Amadou Niaouro Oumarou Ali Diallo 《Open Journal of Nephrology》 2024年第3期340-349,共10页
Introduction: Studies have been conducted on nephrotic syndrome in Niger. The study aimed to determine the histological and etiological aspects of nephrotic syndrome. Patients and Method: This was a retrospective stud... Introduction: Studies have been conducted on nephrotic syndrome in Niger. The study aimed to determine the histological and etiological aspects of nephrotic syndrome. Patients and Method: This was a retrospective study from February 1st, 2018 to January 31st, 2024. All patients with nephrotic syndrome who underwent renal biopsy were included. Samples were analyzed at the anatomy-cytology pathology laboratory of the Faculty of Medicine in Dakar (Senegal). The variables studied included clinical, biological, histological and etiological characteristics. Data were analyzed using Excel 2013 and Epi-info 7.2.0 software. Results: The study included 119 patients with nephrotic syndrome. Prevalence of nephrotic syndrome was 11.24%. The male-to-female ratio was 2.25:1. The mean age at diagnosis was between 34.5 ± 18.84 years. Edema was the reason for admission in 40.34% of cases. The nephrotic syndrome was impure in 63.86% of cases. Nine histological lesions were identified. Focal and segmental glomerulosclerosis (40.09%), minimal change disease (23.53%), membranous nephropathy (13.45%), diabetic nephropathy (10.92%), membranous proliferative glomerulonephritis (3.36%), acute glomerulonephritis (3.36%), glomerular thrombotic microangiopathy (2.52%), non-IgA mesengial proliferative glomerulonephritis (1.68%) and amyloidosis (0.84%). Nephrotic syndrome was primary in 57.98% of cases. Secondary etiologies were dominated by diabetes (11.76%), followed by hepatitis B virus (9.24%), lupus, lymphoma, malaria, syphilis, cryoglobulinemia, sickle cell disease and HIV. Conclusion: Future studies should investigate the causes of glomerulopathy secondary to chronic tubulointerstitial lesions. 展开更多
关键词 Nephrotic Syndrome Anatomopathology Niamey General reference Hospital
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Defining the We-map Reference Frames and Providing Mathematical Expressions for Transformation Relations
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作者 WANG Xiaolong YAN Haowen +2 位作者 WANG Zhuo MA Wenjun YU Yitao 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第3期76-88,共13页
We-map is an interactive mobile map that can be easily communicated and applied on personal electronic devices,such as personal computers and mobile phones.Therefore,the study of direction systems and coordinate syste... We-map is an interactive mobile map that can be easily communicated and applied on personal electronic devices,such as personal computers and mobile phones.Therefore,the study of direction systems and coordinate systems is critical,and exploring reference frames is essential in direction and coordinate systems.Despite its significance,existing research on We-map lacks specific solutions for the exploration of reference frames is indispensable for the establishment of accurate direction and coordinate systems.In this paper,we endeavor to address this gap by elucidating the significance of We-map reference frames,defining them with mathematical constraints,summarizing their nature and characteristics,deriving their transformation relationships and representing them through mathematical formulars and equations.Our work contributes to the fundamental theory of We-map and provides valuable systems and support for the mathematical foundation of We-map,map production,and platform development.Ultimately,this research serves to advance the development of We-map. 展开更多
关键词 We-map reference frames spatial direction relation coordinate system
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Review of Two Years of Surgical Activities of the General Surgery Department of the Reference Health Center of Commune I of Bamako Mali
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作者 Tounkara Cheickna Cisse Amadou Beydi +5 位作者 Samake Hamidou Diarra Issaka Sanogo Modibo Diarra Bogoba Doumbia Seydou Yena Sadio 《Surgical Science》 2024年第4期195-206,共12页
The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristic... The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristics of the operated patients, to determine the main pathologies encountered and to evaluate qualitatively the result of the treatment. In order to improve performance, and the quality of care, and to identify common pathologies in the surgical department, we undertook a retrospective study on surgical activities from January 2009 to December 2010. At the end of this study, out of 474 men and 187 women (equal sex ratio 2.53);we were able to determine the frequency of surgical pathologies. Farmers, housewives and pupils/students were the most represented with 25.9% respectively;20% and 13.3%. The most frequently observed pathologies were wall hernia (44.8%), prostate adenoma (12%) and acute appendicitis (10.5%). The average length of hospitalization was 3.43 days. Infectious complications affected 25 patients (3.8% of cases) and a death rate of 0.45% (i.e. 3 patients). The average cost of care was 53,500 FCFA. Indeed, the reality of surgical practice in health centers was not the same because of the level of skills of practicing surgeons. 展开更多
关键词 Assessment Surgical Activities 2 Years reference Health Center of Commune I BAMAKO
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RPLP0/TBP are the most stable reference genes for human dental pulp stem cells under osteogenic differentiation
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作者 Daniel B Ferreira Leticia M Gasparoni +1 位作者 Cristiane F Bronzeri Katiucia B S Paiva 《World Journal of Stem Cells》 SCIE 2024年第6期656-669,共14页
BACKGROUND Validation of the reference gene(RG)stability during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data normalisation.Commonly,in an unreliable way,... BACKGROUND Validation of the reference gene(RG)stability during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data normalisation.Commonly,in an unreliable way,several studies use genes involved in essential cellular functions[glyceraldehyde-3-phosphate dehydro-genase(GAPDH),18S rRNA,andβ-actin]without paying attention to whether they are suitable for such experimental conditions or the reason for choosing such genes.Furthermore,such studies use only one gene when Minimum Information for Publication of Quantitative Real-Time PCR Experiments guidelines recom-mend two or more genes.It impacts the credibility of these studies and causes dis-tortions in the gene expression findings.For tissue engineering,the accuracy of gene expression drives the best experimental or therapeutical approaches.We cultivated DPSCs under two conditions:Undifferentiated and osteogenic dif-ferentiation,both for 35 d.We evaluated the gene expression of 10 candidates for RGs[ribosomal protein,large,P0(RPLP0),TATA-binding protein(TBP),GAPDH,actin beta(ACTB),tubulin(TUB),aminolevulinic acid synthase 1(ALAS1),tyro-sine 3-monooxygenase/tryptophan 5-monooxygenase activation protein,zeta(YWHAZ),eukaryotic translational elongation factor 1 alpha(EF1a),succinate dehydrogenase complex,subunit A,flavoprotein(SDHA),and beta-2-micro-globulin(B2M)]every 7 d(1,7,14,21,28,and 35 d)by RT-qPCR.The data were analysed by the four main algorithms,ΔCt method,geNorm,NormFinder,and BestKeeper and ranked by the RefFinder method.We subdivided the samples into eight subgroups.RESULTS All of the data sets from clonogenic and osteogenic samples were analysed using the RefFinder algorithm.The final ranking showed RPLP0/TBP as the two most stable RGs and TUB/B2M as the two least stable RGs.Either theΔCt method or NormFinder analysis showed TBP/RPLP0 as the two most stable genes.However,geNorm analysis showed RPLP0/EF1αin the first place.These algorithms’two least stable RGs were B2M/GAPDH.For BestKeeper,ALAS1 was ranked as the most stable RG,and SDHA as the least stable RG.The pair RPLP0/TBP was detected in most subgroups as the most stable RGs,following the RefFinfer ranking.CONCLUSION For the first time,we show that RPLP0/TBP are the most stable RGs,whereas TUB/B2M are unstable RGs for long-term osteogenic differentiation of human DPSCs in traditional monolayers. 展开更多
关键词 Dental pulp stem cells reference gene Housekeeping gene Endogenous gene Osteogenic differentiation RefFinder
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Equalization Reconstruction Algorithm Based on Reference Signal Frequency Domain Block Joint for DTMB-Based Passive Radar
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作者 Shuai Ma Zeqi Yang +2 位作者 Hua Zhang Yiheng Liu Xiaode Lyu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第1期41-53,共13页
Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small... Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference signals.In the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small(LSS)target detection,a novel frequency domain block joint equalization algorithm is presented in this article.From the DTMB signal frame structure and channel multipath transmission characteristics,this article adopts a unconventional approach where the delay and frame structure of each DTMB signal frame are reconfigured to create a circular convolution block,facilitating concurrent fast Fourier transform(FFT)calculations.Following equalization,an inverse fast Fourier transform(IFFT)-based joint output and subsequent data reordering are executed to finalize the equalization process for the DTMB signal.Simulation and measured data confirm that this algorithm outperforms conventional techniques by reducing signal errors rate and enhancing real-time processing.In passive radar LSS detection,it effectively suppresses multipath and noise through frequency domain equalization,reducing false alarms and improving the capabilities of weak target detection. 展开更多
关键词 passive radar frequency domain equalization reference signal reconstruction digital terrestrial multimedia broadcasting(DTMB)
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CTCFL/RPS3A通过抑制内质网应激减少神经元细胞凋亡缓解阿尔兹海默症大鼠认知功能障碍实验研究
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作者 孟清琳 潘娜 +3 位作者 刘养凤 苟英之 吴雅欣 赵锦华 《陕西医学杂志》 CAS 2024年第10期1314-1319,1325,共7页
目的:探究RPS3A在阿尔兹海默症(AD)中的作用及其分子机制。方法:通过将Aβ注射到大鼠双侧海马区,构建AD模型。采用RPS3A的腺病毒载体(Ad-RPS3A)注射AD大鼠,饲养14 d后通过水迷宫测试评估大鼠的学习与记忆能力,通过Y迷宫测试评估大鼠的... 目的:探究RPS3A在阿尔兹海默症(AD)中的作用及其分子机制。方法:通过将Aβ注射到大鼠双侧海马区,构建AD模型。采用RPS3A的腺病毒载体(Ad-RPS3A)注射AD大鼠,饲养14 d后通过水迷宫测试评估大鼠的学习与记忆能力,通过Y迷宫测试评估大鼠的空间探索能力。此外,采用RPS3A的过表达载体(RPS3A)、shRNA(sh-RPS3A)、CTCFL的过表达载体(CTCFL)、shRNA(sh-CTCFL)分别转染神经元HT22细胞48 h,然后采用30μmol/L的Aβ处理细胞24 h。使用JASPAR预测CTCFL在RPS3A启动子的结合,并通过Ch-IP分析和荧光素酶报告基因分析进行验证。RT-qPCR检测过表达和沉默效率;Western blot检测RPS3A和CTCFL蛋白,以及内质网应激相关蛋白和凋亡相关蛋白表达水平;CCK-8和流式细胞术分别检测细胞活力和细胞凋亡率。结果:与假手术组相比,AD模型组大鼠海马组织中RPS3A的mRNA和蛋白水平显著下调。Aβ诱导的HT22细胞中RPS3A蛋白表达显著下调;过表达RPS3A促进HT22细胞增殖,抑制Aβ诱导的细胞凋亡,降低Cleaved caspase-3和Bax蛋白表达,促进Bcl-2蛋白表达,抑制内质网应激相关蛋白CRP78、CHOP、ATF6和XBP1表达,降低IRE1和PERK磷酸化水平。机制研究显示CTCFL通过与RPS3A启动子区结合,促进RPS3A转录激活。过表达CTCFL促进RPS3A蛋白表达;而沉默CTCFL作用相反。体内结果显示,过表达RPS3A降低AD大鼠抵达平台的时间、到达平台距离以及第一次进入SW区的时间,增加大鼠自发交替率和进入新异臂次数的比值,改善Aβ诱导的AD大鼠的学习与记忆能力障碍和空间探索能力障碍。结论:CTCFL介导的RPS3A通过内质网应激诱导神经元细胞凋亡,促进阿尔兹海默病小鼠的认知功能障碍。 展开更多
关键词 阿尔兹海默症 认知功能障碍 神经元凋亡 rps3A CTCFL 内质网应激
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A Reference Vector-Assisted Many-Objective Optimization Algorithm with Adaptive Niche Dominance Relation
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作者 Fangzhen Ge Yating Wu +1 位作者 Debao Chen Longfeng Shen 《Intelligent Automation & Soft Computing》 2024年第2期189-211,共23页
It is still a huge challenge for traditional Pareto-dominatedmany-objective optimization algorithms to solve manyobjective optimization problems because these algorithms hardly maintain the balance between convergence... It is still a huge challenge for traditional Pareto-dominatedmany-objective optimization algorithms to solve manyobjective optimization problems because these algorithms hardly maintain the balance between convergence and diversity and can only find a group of solutions focused on a small area on the Pareto front,resulting in poor performance of those algorithms.For this reason,we propose a reference vector-assisted algorithmwith an adaptive niche dominance relation,for short MaOEA-AR.The new dominance relation forms a niche based on the angle between candidate solutions.By comparing these solutions,the solutionwith the best convergence is found to be the non-dominated solution to improve the selection pressure.In reproduction,a mutation strategy of k-bit crossover and hybrid mutation is used to generate high-quality offspring.On 23 test problems with up to 15-objective,we compared the proposed algorithm with five state-of-the-art algorithms.The experimental results verified that the proposed algorithm is competitive. 展开更多
关键词 Many-objective optimization evolutionary algorithm Pareto dominance reference vector adaptive niche
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大口径天线3-RPS驱动机构结构优化设计与分析
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作者 吴凯 郑飞 梅贵凤 《现代机械》 2024年第5期14-19,86,共7页
采用并联机构替换现有的方位-俯仰式串联机构作为反射面天线的驱动机构可以满足其位姿调整的功能,并有效改善反射面天线整体结构的轻量化效果。目前少有将并联机构应用于大口径天线的分析与实际工程应用案例,故需要对承受较大载荷的并... 采用并联机构替换现有的方位-俯仰式串联机构作为反射面天线的驱动机构可以满足其位姿调整的功能,并有效改善反射面天线整体结构的轻量化效果。目前少有将并联机构应用于大口径天线的分析与实际工程应用案例,故需要对承受较大载荷的并联机构展开力学分析并对其结构进行优化,从而使其满足承载与运动精度的要求。针对3-RPS并联机构承受较大载荷时支链的结构方案展开优化设计并进行有限元仿真分析。首先,对3-RPS并联机构展开静力学分析,得到在动平台承受一定载荷的情况下机构各个支链的受力特性;其次,在给定机构基本尺寸参数及活动范围要求下,对3-RPS并联机构支链的结构方案进行设计,针对并联机构支链弯曲变形较为严重的情况提出了并联液压缸的结构方案;最后,对并联液压缸结构方案进行了优化以及稳定性分析。结果表明,优化后的并联液压缸方案各项性能指标均优于原有方案,且满足稳定性安全性要求,为实际的工程应用提供参考。 展开更多
关键词 3-rps并联机构 多级液压缸 有限元分析 优化设计
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超级黑胶唱盘New Reference有多硬核? THORENS多能仕总裁Gunter Kurten先生告诉你
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作者 小路 《视听前线》 2024年第9期78-79,共2页
德国THORENS(多能仕),自1883年创立以来,已拥有超过140年的辉煌历史,是全球首屈一指的黑胶唱盘品牌之一。值此140周年庆典之际,THORENS于2023年隆重推出了新一代的旗舰产品——New Reference超级黑胶唱盘。
关键词 旗舰产品 reference 黑胶 TH NS 辉煌历史
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Design of MC9 Test Equipment for Inertial Reference System
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作者 ZHANG Haowen GUAN Hongyang WANG Shuangjia 《International Journal of Plant Engineering and Management》 2024年第2期115-128,共14页
Inertial reference system is one of the airborne equipment.According to the requirements of SAE ARP4754A Guidelines for Development of Civil Aircraft and Systems,MC9 equipment qualification test is needed to verify th... Inertial reference system is one of the airborne equipment.According to the requirements of SAE ARP4754A Guidelines for Development of Civil Aircraft and Systems,MC9 equipment qualification test is needed to verify that the inertial reference system can perform reservation function under specified service conditions.That is,the inertial reference system shall pass certain environmental tests specified in DO⁃160G.Some tests are faced with the problem that the test equipment should have the function requirements of isolation protection and load simulation.Therefore,a kind of test equipment which can provide isolation protection and simulate load function in the test is designed. 展开更多
关键词 inertial reference system MC9 isolation protection simulated load
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一个传奇的品牌,一个经典的系列 KEF与TheReference系列的故事
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作者 家祺 《视听前线》 2024年第1期2-7,共6页
回顾2023年,KEF的产品又再斩获众多不同定位、不同类型的各种Hi-Fi音响奖项。在更新MAT技术后,KEF全线新Meta系列在音质方面的提升是备受肯定的。其中最受瞩目的自然是KEF当家的Reference系列了。Reference (参考)系列作为KEF产品线中... 回顾2023年,KEF的产品又再斩获众多不同定位、不同类型的各种Hi-Fi音响奖项。在更新MAT技术后,KEF全线新Meta系列在音质方面的提升是备受肯定的。其中最受瞩目的自然是KEF当家的Reference系列了。Reference (参考)系列作为KEF产品线中一个非常重要的高端系列,历经多次变革,至今依然是KEF产品线当中最受发烧友欢迎的系列。它不仅是嫡传KEF每个时期应用于旗舰级先进技术的产品,更是KEF最新技术的普及应用和向下移植的承载者。这个刚刚迈过第50个年头的经典系列在这么多年来能够持续获得发烧友和媒体的喜爱实属不易,这个系列是如何一步一步成为经典的?我们来回顾一下KEF这个品牌与参考系列的发展。 展开更多
关键词 KEF 旗舰级 reference 承载者 产品线 音质 普及应用 品牌
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一切皆有可能 测试Consonance Reference CDS8音乐播放器
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作者 克里斯蒂安·拜尔 Yilan(编译) Ivy Li(编译) 《视听前线》 2024年第10期35-37,共3页
以前,我从未想过听CD会过时,但在无载体媒体时代,情况已经如此。幸运的是,一群执着的音响发烧友还在坚持。ORERA Consonance Re horee a OPERA Consonance Reference CDS8这款CD、数码流播放器,不仅可以播放CD,而且它是以非常高的水准... 以前,我从未想过听CD会过时,但在无载体媒体时代,情况已经如此。幸运的是,一群执着的音响发烧友还在坚持。ORERA Consonance Re horee a OPERA Consonance Reference CDS8这款CD、数码流播放器,不仅可以播放CD,而且它是以非常高的水准来播放CD,名副其实的好产品,可以与Advance Acoustics、Creek、AVM等这些品牌的产品齐名。 展开更多
关键词 音乐播放器 音响发烧友 一切皆有可能 无载体 reference CDS AVM
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The China Seismological Reference Model project 被引量:4
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作者 LianXing Wen Sheng Yu 《Earth and Planetary Physics》 CAS CSCD 2023年第5期521-532,共12页
The importance of developing high-resolution seismic models to improve understanding of tectonic processes and enhance seismic hazard mitigation programs,along with the rapid expansion of seismic coverage in China,cal... The importance of developing high-resolution seismic models to improve understanding of tectonic processes and enhance seismic hazard mitigation programs,along with the rapid expansion of seismic coverage in China,called for a seismological reference model to be established in China.The China Seismological Reference Model(CSRM)project was initiated by the National Natural Science Foundation of China with two primary goals:(1)the CSRM would serve as a primary source for the current state of seismological research in China,and(2)the seismic data and constraints used to construct the CSRM would be used as a backbone open-access cyberinfrastructure for future research in seismology.The CSRM project was also intended to promote data exchange and scientific collaboration in seismology in China.Accordingly,two parallel efforts of the project are being pursued:(1)construction of the CSRM,and(2)development of a CSRM product center.The CSRM is jointly constrained by various types of seismic constraints extracted from the seismic data recorded at 4511 seismic stations in continental China following a top-down approach,with the seismic structures in the shallower part of the Earth constrained first.Construction of the CSRM involves three preparation steps:(1)building datasets of various seismic constraints from the seismic data,(2)developing a method to incorporate the constraints of surface wave observations from regional earthquakes into the inversion of the seismic structure,and(3)constructing high-resolution pre-CSRM seismic models of the velocity structure in the shallow crust and the Pn-velocity structure in the uppermost mantle.In the final process,the CSRM will be constructed by jointly inverting all the seismic constraints using the pre-CSRM models as starting models or a priori structures.The CSRM product center(http://chinageorefmodel.org)archives and distributes three types of products:CSRM models,the Level 1 original seismic data used to extract seismic constraints in the construction of the CSRM,and Level 2 data on the seismic constraints derived from the Level 1 data and the inferred earthquake parameters in the construction of the CSRM.The CSRM product center has archived 141 TB of Level 1 data from 1120 permanent broadband stations in the China Seismic Network Center and 3391 temporary stations from various institutions and data centers around the world,as well as 140 GB of Level 2 data on various seismic constraints and inferred event parameters from the construction of the CSRM.The CSRM is expected to provide significant insights into the composition and tectonic dynamics in continental China and to enhance the capability of various seismic hazard mitigation programs in China from near real-time rapid determination of earthquake parameters to an earthquake early warning system.The CSRM could also provide guidance for focuses in future seismological research and the design of future active and passive seismic experiments in China.Several focuses are suggested for future seismological research in China,along with the building of a national cyberinfrastructure to sustain and expand the operations of the CSRM project. 展开更多
关键词 China Seismological reference Model seismic structure seismic hazard TECTONICS continental China
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桔梗科rps2基因簇断裂对进化速率的影响
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作者 栗锦烨 平晶耀 +2 位作者 崔贵峰 苏应娟 王艇 《植物科学学报》 CAS CSCD 北大核心 2023年第3期333-342,共10页
保守的rps2基因簇(rps2-atpI-atpH-atpF-atpA)在桔梗科的叶绿体基因组中发生了断裂。为探究该基因簇断裂后,相关基因的进化速率是否发生变化,本研究选取50种桔梗科植物和2种睡菜科植物的叶绿体基因组序列进行系统发育关系的构建,对rps2... 保守的rps2基因簇(rps2-atpI-atpH-atpF-atpA)在桔梗科的叶绿体基因组中发生了断裂。为探究该基因簇断裂后,相关基因的进化速率是否发生变化,本研究选取50种桔梗科植物和2种睡菜科植物的叶绿体基因组序列进行系统发育关系的构建,对rps2基因簇相关基因的进化速率、选择压力以及适应性进化过程进行分析。结果显示,桔梗科中rps2基因簇发生断裂的物种均来自风铃草亚科,且在系统发育树上组成单系分支;与未断裂物种相比,断裂物种中相关基因的进化速率均值降低;基因间的非同义替换速率存在显著差异。适应性进化分析中,位点模型在atpI和rps2基因中检测到正选择位点。本研究结果表明基因簇断裂可能具有系统发育意义,基因簇断裂后进化速率会发生改变,不同基因也经历了不同的进化历程。 展开更多
关键词 rps2基因簇 桔梗科 进化速率 选择压力 适应性进化
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RPS4X在肺腺癌患者中的表达情况及临床意义
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作者 陈广靖 葛孝忠 +3 位作者 奚宽平 费书文 潘春峰 朱青松 《中国肿瘤外科杂志》 CAS 2023年第1期13-18,共6页
目的探讨RPS4X在肺腺癌患者中的表达及其潜在的临床意义。方法从cBioPortal、TCGA数据库分析差异表达基因;收集肺腺癌组织,采用qRT-PCR检测RPS4X的表达水平;结合临床资料论证RPS4X的表达情况、临床意义,并采用Kaplan-Meier曲线分析患者... 目的探讨RPS4X在肺腺癌患者中的表达及其潜在的临床意义。方法从cBioPortal、TCGA数据库分析差异表达基因;收集肺腺癌组织,采用qRT-PCR检测RPS4X的表达水平;结合临床资料论证RPS4X的表达情况、临床意义,并采用Kaplan-Meier曲线分析患者的总生存期,采用Cox模型分析单因素和多因素指标。结果RPS4X在肺腺癌中高表达,且在女性肺腺癌患者中明显高于男性患者。进一步分析发现,与肿瘤大小≤3 cm组比,RPS4X在>3 cm组中呈高表达;与低分化组比,RPS4X在中分化、高分化组中呈低表达;与无淋巴结转移组比,RPS4X在有淋巴结转移组中高表达;高表达RPS4X的肺腺癌患者较低表达RPS4X患者预后差,可作为患者预后的独立预测因素。结论RPS4X在肺腺癌患者中表达显著升高,且与性别、肿瘤大小、分化程度、淋巴结转移有关,可作为诊治肺腺癌潜在的新靶标。 展开更多
关键词 rps4X 肺腺癌 预后
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