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Book Announcement of L. Celentano, Robust Tracking Controllers Design with Generic References for Continuous and Discrete Uncertain Linear SISO Systems, LAP LAMBERT Academic Publishing, 2012 被引量:1
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作者 Laura Celentano 《International Journal of Modern Nonlinear Theory and Application》 2014年第2期1-3,共3页
In this book new results on controller design techniques for the tracking of generic reference inputs are presented. They allow the design of a controller for an uncertain process, either continuous or discrete-time, ... In this book new results on controller design techniques for the tracking of generic reference inputs are presented. They allow the design of a controller for an uncertain process, either continuous or discrete-time, without zeros, and with measurable state. The controller guarantees that the control system is Type 1 and has the desired constant gain and poles or that the control system tracks, with a specified maximum error and with a specified maximum time constant, a generic reference with bounded derivative (variation in the discrete-time case), also in the presence of a generic disturbance with bounded derivative (variation). In addition, it is considered the case in which the reference is known a priori. The utility and the efficiency of the proposed methods are illustrated with attractive and significant examples of motion control and temperature control. This book is useful for the design of control systems, especially for manufacturing systems, that are versatile, fast, precise and robust. 展开更多
关键词 Robust Tracking Controllers Design CONTINUOUS and DISCRETE UNCERTAIN LINEAR SISO Systems Generic references
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The UK Education System and References for China
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作者 李欢欢 《海外英语》 2011年第15期288-289,298,共3页
The UK education has a long history and is internationally accepted for its qualifications and teaching standards. This essay firstly gives an introduction about the development of British education since the last cen... The UK education has a long history and is internationally accepted for its qualifications and teaching standards. This essay firstly gives an introduction about the development of British education since the last century, then discusses the basic structure of British education system and finally suggests some references for our education. 展开更多
关键词 The UK EDUCATION SYSTEM the DEVELOPMENT of BRITISH EDUCATION references for China
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Environmeutal sciences update references in Chinese journals
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《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1993年第1期124-126,共3页
Selected from Acta Scientiac Circumstantiac,ISSN 0253~2468;Environmental Chemistry,ISSN 0254-6108;Acra Ecologia Sinica,ISSN 1000-0933(The address giben in a reference is that of the first named author)
关键词 ISSN Environmeutal sciences update references in Chinese journals
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General coarsened measurement references for revelation of a classical world
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作者 谢东 徐春玲 王安民 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第11期133-137,共5页
It has been found that for a fixed degree of fuzziness in the coarsened references of measurements,the quantum-toclassical transition can be observed independent of the macroscopicity of the quantum state.We explore a... It has been found that for a fixed degree of fuzziness in the coarsened references of measurements,the quantum-toclassical transition can be observed independent of the macroscopicity of the quantum state.We explore a general situation that the degree of fuzziness can change with the rotation angle between two states(different rotation angles represent different references).The fuzziness of reference comes from two kinds of fuzziness:the Hamiltonian(rotation frequency)and the timing(rotation time).For the fuzziness of the Hamiltonian alone,the degree of fuzziness for the reference will change with the rotation angle between two states,and the quantum effects can still be observed with any degree of fuzziness of Hamiltonian.For the fuzziness of timing,the degree of the coarsening reference is unchanged with the rotation angle.During the rotation of the measurement axis,the decoherence environment can also help the classical-to-quantum transition due to changing the direction of the measurement axis. 展开更多
关键词 fuzziness rotation Hamiltonian references unitary timing comes unchanged alone operators
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Neonatal References: Epidemiology and Prognosis in a Malian Context
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作者 Fatoumata L. F. Diakité Djénèba Konaté +21 位作者 Nouhoum L. Traoré Noel Banou Lala N. Sidibé Oumar Coulibaly Belco Maiga Karamoko Sacko Fousseyni Traoré Abdoul K. Doumbia Hawa G. Diall Leila Maiga Ibrahim Ahamadou Alou Traoré Adama Koné Guediouma Dembélé Djita Ba-Sidibé Pierre Togo Adama Dembélé El Mouloud Cissé Abdoul A. Diakité Boubacar Togo Mariam Sylla Fatoumata Dicko-Traoré 《Open Journal of Pediatrics》 2021年第3期479-489,共11页
Neonatal mortality remains a public health problem in Mali. The neonatal referral is a systemic factor determining the neonatal prognosis. This work was initiated to determine the frequency of neonatal referrals and t... Neonatal mortality remains a public health problem in Mali. The neonatal referral is a systemic factor determining the neonatal prognosis. This work was initiated to determine the frequency of neonatal referrals and to determine their prognosis. </span><b><span style="font-family:Verdana;">Patients and Methods: </span></b><span style="font-family:Verdana;">A cross-sectional study was carried out from November 1, 2019 to January 31, 2020 in the neonatology service of the pediatrics department of the Gabriel Toure University Hospital in Bamako. All newborns referred by another health structure in the country were included in this stud. All newborns referred by another health structure in the country were included in this study. To determine the risk factors related to the neonatal referral, we performed univariate and multivariate analyzes to determine the odds ratios and fitted with a significant p probability if p <</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">0.05 and the 95% confidence interval. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> The frequency of referrals was 54.3%.</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Newborns came from basic structures in 19.3% of cases, from tertiary structures in 6.7%.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">The main reason for transfer was prematurity (40.2%) followed by perinatal anoxia (15.3%), malformations (15.3%), respiratory distress (15.2%) and infection neonatal (9.1%). The ambulance was the primary means of transfer in 71.3%.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">In 80% of cases the transfer had been made within the first 24 hours of life. On admission, a third of the newborns (31.1%) were less than 1500</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">g, hypothermic in 43.8% and febrile in 15.1%.</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">The evolution was marked by 40.2% of deaths. The analysis of prognostic factors, allowed us to observe that the more the newborn is premature or of low weight the more risk of death was very high with respectively 18.5 times </span><span style="font-family:Verdana;">in the less than 28 week</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> of amenorrhea (WA) (ORa = 18</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">5;CI = 1.9</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">180;</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">p = 0.012) and 6.6 times in those less than 1000g (ORa = 6.6;CI = 1.4</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">29.7;p = 0.015). Likewise, any change in body temperature increased risk of death by 1.9 times compared to normothermia. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The establishment of a neonatal referral system is necessary to reduce neonatal mortality in our context. 展开更多
关键词 Neonatal references EPIDEMIOLOGY PROGNOSIS Malian Context
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Evaluation of Expression Stability of Candidate References Genes among Green and Yellow Pea Cultivars (<i>Pisum sativum</i>L.) Subjected to Abiotic and Biotic Stress
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作者 Gopesh C. Saha George J. Vandemark 《American Journal of Plant Sciences》 2012年第2期235-242,共8页
Dry pea (Pisum sativum L.) is grown as human and animal feed throughout the world. Large yield losses in pea due to biotic and abiotic stresses compel an improved understanding of mechanisms of stress tolerance and ge... Dry pea (Pisum sativum L.) is grown as human and animal feed throughout the world. Large yield losses in pea due to biotic and abiotic stresses compel an improved understanding of mechanisms of stress tolerance and genetic determinants conditioning these tolerances. The availability of stably expressed reference genes is a prerequisite for examining differential gene expression. The objective of this study was to examine the expression profile of several candidate reference genes across a broad range of commercial pea cultivars. Expression profiles of five candidate reference genes;18s rRNA, actin, TIF, β tubulin-2 and β tubulin-3 were examined. Relative quantifications of candidate reference genes were estimated from control plants, plants after 48 h of cold treatment, and plants 24 and 48 h after inoculation with Sclerotinia sclerotiorum, the causal agent of white mold disease of pea. RT-qPCR was performed on cDNA synthesized from three food grade spring peas, Ariel, Aragorn, and Sterling, and two spring yellow peas, Delta and Universal, which are used as animal feed. Analysis of variance (ANOVA) of CT values demonstrated significant variation between varieties and treatments under cold and disease conditions. The most abundant transcripts among tested reference genes were for 18s rRNA. Stability analysis indicated that TIF and β tubulin-3 genes were the most stably expressed candidate genes under both cold and disease stress and could serve as reference genes across a wide range of pea cultivars. 展开更多
关键词 RT-qPCR REFERENCE Genes SCLEROTINIA sclerotiorum Cold Treatment PISUM sativum
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A Brief Analysis on Citation Forms of English Journal Titles in References of Animal Science and Veterinary Medicine Journals
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作者 Ren Peng Bai Yongping +2 位作者 Guo Yunyan Cheng Jinhua Li Shuchao 《Animal Husbandry and Feed Science》 CAS 2014年第5期271-275,共5页
In this paper,the problems of citation forms of English journal titles in references of animal science and veterinary medicine journals were described and analyzed. And the English names of animal science and veterina... In this paper,the problems of citation forms of English journal titles in references of animal science and veterinary medicine journals were described and analyzed. And the English names of animal science and veterinary medicine journals and corresponding abbreviations were listed for reference by authors. 展开更多
关键词 Reference Abbreviation of journal titles Animal Science and Veterinary Medicine
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Comparison between English and Chinese Repeated References to the Same Thing and Parallel Structure
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作者 赵丽红 《海外英语》 2013年第11X期259-261,共3页
Chinese and English are two very different languages; the former belongs to the Sino-Tibetan Language Family and the latter the Indo-European Language Family. In terms of textual organization, they show substantial di... Chinese and English are two very different languages; the former belongs to the Sino-Tibetan Language Family and the latter the Indo-European Language Family. In terms of textual organization, they show substantial differences. Chinese is mainly a pragmatic, paratactic and topic-prominent language, while English a grammatical, hypotactic and subject-prominent language. This thesis gives a contrastive study of two problems in English and Chinese. They are repeated references to the same thing and parallel structure. In this way, the translation work will be more succinct and smooth. 展开更多
关键词 DIFFERENCES in ENGLISH and CHINESE repeated refere
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Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints 被引量:1
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作者 Jin-Xi Zhang Kai-Di Xu Qing-Guo Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1557-1565,共9页
The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requ... The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this paper.Herein, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings. 展开更多
关键词 Nonlinear systems output constraints prescribed performance reference tracking time delays
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A 16-bit 18-MSPS flash-assisted SAR ADC with hybrid synchronous and asynchronous control logic 被引量:1
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作者 Junyao Ji Xinao Ji +5 位作者 Ziyu Zhou Zhichao Dai Xuhui Chen Jie Zhang Zheng Jiang Hong Zhang 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期3-12,共10页
This paper presents a 16-bit,18-MSPS(million samples per second)flash-assisted successive-approximation-register(SAR)analog-to-digital converter(ADC)utilizing hybrid synchronous and asynchronous(HYSAS)timing control l... This paper presents a 16-bit,18-MSPS(million samples per second)flash-assisted successive-approximation-register(SAR)analog-to-digital converter(ADC)utilizing hybrid synchronous and asynchronous(HYSAS)timing control logic based on an on-chip delay-locked loop(DLL).The HYSAS scheme can provide a longer settling time for the capacitive digital-to-analog converter(CDAC)than the synchronous and asynchronous SAR ADC.Therefore,the issue of incomplete settling or ringing in the DAC voltage for cases of either on-chip or off-chip reference voltage can be solved to a large extent.In addition,the fore-ground calibration of the CDAC’s mismatch is performed with a finite-impulse-response bandpass filter(FIR-BPF)based least-mean-square(LMS)algorithm in an off-chip FPGA(field programmable gate array).Fabricated in 40-nm CMOS process,the proto-type ADC achieves 94.02-dB spurious-free dynamic range(SFDR),and 75.98-dB signal-to-noise-and-distortion ratio(SNDR)for a 2.88-MHz input under 18-MSPS sampling rate. 展开更多
关键词 SAR ADC control logic reference ringing DAC incomplete settling
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The AME2012 atomic mass evaluation(Ⅱ).Tables,graphs and references 被引量:34
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作者 M.Wang G.Audi +4 位作者 A.H.Wapstra F.G.Kondev M.MacCormick X.Xu B.Pfeiffer 《Chinese Physics C》 SCIE CAS CSCD 2012年第12期1287-1602,共316页
This paper is the first of two articles (Part I and Part II) that presents the results of the new atomic mass evaluation, AME2012. It includes complete information on the experimental input data (including not used... This paper is the first of two articles (Part I and Part II) that presents the results of the new atomic mass evaluation, AME2012. It includes complete information on the experimental input data (including not used and rejected ones), as well as details on the evaluation procedures used to derive the tables with recommended values given in the second part. This article describes the evaluation philosophy and procedures that were implemented in the selection of specific nuclear reaction, decay and mass-spectrometer results. These input values were entered in the least-squares adjustment procedure for determining the best values for the atomic masses and their uncertainties. Calculation procedures and particularities of the AME are then described. All accepted and rejected data, including outweighed ones, are presented in a tabular format and compared with the adjusted values (obtained using the adjustment procedure). Differences with the previous AME2003 evaluation are also discussed and specific information is presented for several cases that may be of interest to various AME users. The second AME2012 article, the last one in this issue, gives a table with recommended values of atomic masses, as well as tables and graphs of derived quantifies, along with the list of references used in both this AME2012 evaluation and the NUBASE2012 one (the first paper in this issue). 展开更多
关键词 AME Tables graphs and references
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基于0-1膨胀二项分布的客观贝叶斯分析
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作者 吴懿祺 肖翔 古晞 《计算机应用与软件》 北大核心 2024年第4期46-52,59,共8页
在医疗卫生、金融证券等应用领域,经常会同时出现零观测值、一观测值较多的情况。为更好地拟合这类数据,提出一种0-1膨胀二项分布模型并进行客观贝叶斯分析。采用数据扩充策略,基于完全似然函数,得到Jeffreys先验和reference先验。采用W... 在医疗卫生、金融证券等应用领域,经常会同时出现零观测值、一观测值较多的情况。为更好地拟合这类数据,提出一种0-1膨胀二项分布模型并进行客观贝叶斯分析。采用数据扩充策略,基于完全似然函数,得到Jeffreys先验和reference先验。采用WinBUGS软件和R软件进行数值模拟,设定不同的样本量和参数真值,对不同的无信息先验进行评估。对2020年1月28日与2月22日COVID-19死亡人数进行分析,结果表明,在小样本情形下基于客观贝叶斯先验π_(R3)下的拟合效果比π_(R1)和π_(R2)要好。 展开更多
关键词 0-1膨胀二项分布 客观贝叶斯 Jeffreys先验 reference先验 数据扩充
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The space-time references of BeiDou Navigation Satellite System 被引量:4
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作者 Chunhao Han Li Liu +1 位作者 Zhiwu Cai Yuting Lin 《Satellite Navigation》 2021年第1期253-262,共10页
The BeiDou Navigation Satellite System (BDS) is essentially a precise time measurement and time synchronization system for a large-scale space near the Earth. General relativity is the basic theoretical framework for ... The BeiDou Navigation Satellite System (BDS) is essentially a precise time measurement and time synchronization system for a large-scale space near the Earth. General relativity is the basic theoretical framework for the information processing in the master control station of BDS. Having introduced the basic conceptions of relativistic space-time reference systems, the space-time references of BDS are analyzed and the function and acquisition method of the Earth Orientation Parameters (EOP) are briefly discussed. The basic space reference of BDS is BeiDou Coordinate System (BDCS), and the time standard is the BDS Time (BDT). BDCS and BDT are the realizations of the Geocentric Terrestrial Reference System (GTRS) and the Terrestrial Time (TT) for BDS, respectively. The station coordinates in the BDCS are consistent with those in International Terrestrial Reference Frame (ITRF)2014 at the cm-level and the difference in scale is about 1.1 × 10^(−8) . The time deviation of BDT relative to International Atomic Time (TAI) is less than 50 ns and the frequency deviation is less than 2 × 10^(−14) . The Geocentric Celestial Reference System (GCRS) and the solar Barycentric Celestial Reference System (BCRS) are also involved in the operation of BDS. The observation models for time synchronization and precise orbit determination are established within the GCRS framework. The coordinate transformation between BDCS and GCRS is consistent with the International Earth Rotation and Reference Systems Service (IERS). In the autonomous operation mode without the support of the ground master control station, Earth Orientation Parameters (EOP) is obtained by means of long-term prediction and on-board observation. The observa-tion models for the on-board astrometry should be established within the BCRS framework. 展开更多
关键词 BDS BDT Space-time references BeiDou coordinate system Earth orientation parameters
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Evaluating the performance of genomic selection on purebred population by incorporating crossbred data in pigs
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作者 Jun Zhou Qing Lin +10 位作者 Xueyan Feng Duanyang Ren Jinyan Teng Xibo Wu Dan Wu Xiaoke Zhang Xiaolong Yuan Zanmou Chen Jiaqi Li Zhe Zhang Hao Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期639-648,共10页
Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it... Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it was limited by the purebred population.Compared to directly combining two uncorrelated purebred populations to extend the reference population size,it might be more meaningful to incorporate the correlated crossbreds into reference population for genomic prediction.In this study,we simulated purebred offspring(PAS and PBS)and crossbred offspring(CAB)base on real genotype data of two base purebred populations(PA and PB),to evaluate the performance of genomic selection on purebred while incorporating crossbred information.The results showed that selecting key crossbred individuals via maximizing the expected genetic relationship(REL)was better than the other methods(individuals closet or farthest to the purebred population,CP/FP)in term of the prediction accuracy.Furthermore,the prediction accuracy of reference populations combining PA and CAB was significantly better only based on PA,which was similar to combine PA and PAS.Moreover,the rank correlation between the multiple of the increased relationship(MIR)and reliability improvement was 0.60-0.70.But for individuals with low correlation(Cor(Pi,PA or B),the reliability improvement was significantly lower than other individuals.Our findings suggested that incorporating crossbred into purebred population could improve the performance of genetic prediction compared with using the purebred population only.The genetic relationship between purebred and crossbred population is a key factor determining the increased reliability while incorporating crossbred population in the genomic prediction on pure bred individuals. 展开更多
关键词 PIGS crossbred population genomic selection reference population construction relationship
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Deciphering the population structure and genetic basis of growth traits from whole-genome resequencing of the leopard coral grouper(Plectropomus leopardus)
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作者 Shao-Xuan Wu Qi-Fan Zeng +9 位作者 Wen-Tao Han Meng-Ya Wang Hui Ding Ming-Xuan Teng Ming-Yi Wang Pei-Yu Li Xin Gao Zhen-Min Bao Bo Wang Jing-Jie Hu 《Zoological Research》 SCIE CSCD 2024年第2期329-340,共12页
The leopard coral grouper(Plectropomus leopardus)is a species of significant economic importance.Although artificial cultivation of P.leopardus has thrived in recent decades,the advancement of selective breeding has b... The leopard coral grouper(Plectropomus leopardus)is a species of significant economic importance.Although artificial cultivation of P.leopardus has thrived in recent decades,the advancement of selective breeding has been hindered by the lack of comprehensive population genomic data.In this study,we identified over 8.73 million single nucleotide polymorphisms(SNPs)through whole-genome resequencing of 326 individuals spanning six distinct groups.Furthermore,we categorized 226 individuals with high-coverage sequencing depth(≥14×)into eight clusters based on their genetic profiles and phylogenetic relationships.Notably,four of these clusters exhibited pronounced genetic differentiation compared with the other populations.To identify potentially advantageous loci for P.leopardus,we examined genomic regions exhibiting selective sweeps by analyzing the nucleotide diversity(θπ)and fixation index(FST)in these four clusters.Using these high-coverage resequencing data,we successfully constructed the first haplotype reference panel specific to P.leopardus.This achievement holds promise for enabling high-quality,cost-effectiveimputationmethods.Additionally,we combined low-coverage sequencing data with imputation techniques for a genome-wide association study,aiming to identify candidate SNP loci and genes associated with growth traits.A significant concentration of these genes was observed on chromosome 17,which is primarily involved in skeletal muscle and embryonic development and cell proliferation.Notably,our detailed investigation of growth-related SNPs across the eight clusters revealed that cluster 5 harbored the most promising candidate SNPs,showing potential for genetic selective breeding efforts.These findings provide a robust toolkit and valuable insights into the management of germplasm resources and genome-driven breeding initiatives targeting P.leopardus. 展开更多
关键词 Plectropomus leopardus Whole-genome resequencing Growth Haplotype reference panel Single nucleotide polymorphisms
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Styrax japonicus functional genomics:an efficient virus induced gene silencing(VIGS)system
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作者 Gangyu Sun Yiqian Ju +6 位作者 Cuiping Zhang Lulu Li Xinqiang Jiang Xiaoman Xie Yizeng Lu Kuiling Wang Wei Li 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期252-258,共7页
VIGS(Virus-induced gene silencing),a method for posttranscriptional gene silencing,is an effective technique for investigating the activities of genes in plants.Since there is no report for available VIGS system in St... VIGS(Virus-induced gene silencing),a method for posttranscriptional gene silencing,is an effective technique for investigating the activities of genes in plants.Since there is no report for available VIGS system in Styrax japonicus,the application of a VIGS approach that results in a gene knockdown to study gene function is limited.In this study,we compared the characteristics that could affect the viability of VIGS in S.japonicus,including the acetosyringone(AS)concentration,the Agrobacterium’s optical density and the inoculation method.The stable reference genes of S.japonicus were selected to validate the gene’s knockdown by quantitative PCR.As a result,we successfully constructed 2 VIGS systems based on TRV virus:vacuum with AS concentration of 200μmol·L^(-1)and OD600of 0.5,and friction-osmosis with AS concentration of 200μmol·L^(-1)and OD600of 1.0,which silencing efficiency was 83.33%and 74.19%,respectively.The successfully applied VIGS method provides a rapid and effective reverse gene functional analysis approach in S.japonicus to identify unknown gene functions. 展开更多
关键词 Styrax japonicus VIGS Reference gene
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The Application of Permanent Magnet Synchronous Motor with Small Electrical Time Constant in Fiber Positioner
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作者 Shaoxiong Guo Yan Yang +3 位作者 Yanbin Yin Yihu Tang Yang Tian Chao Zhai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期212-222,共11页
With the development of cutting-edge multi-object spectrographs,fiber positioners located in the focal plane are being scaled down in size,and miniature hollow-cup Permanent Magnet motors are now being considered as a... With the development of cutting-edge multi-object spectrographs,fiber positioners located in the focal plane are being scaled down in size,and miniature hollow-cup Permanent Magnet motors are now being considered as a suitable replacement for Faulhaber Precistep stepper motors.However,the small electrical time constant of such coreless motors poses a challenge,as the problem of severe commutation torque ripple in a fiber positioner running a position loop has been tricky.To overcome this challenge,it is advised to increase the Pulse Width Modulation(PWM)frequency as much as possible to mitigate the effects of the current fluctuation.This must be done while ensuring adequate resolution of the PWM generator.By employing a voltage open-loop field-oriented control based on a modulation frequency of 1 MHz,the drive current only costs 25 m A under a 3.3 V power supply.The sine degree of phase current is immaculate,and the repeat positioning accuracy can reach 2μm.Moreover,it is possible to further shrink the bill of devices and the layout area of the Printed Circuit Board,especially in sizesensitive applications.This device has been developed under the new generation of The Large Sky Area MultiObject Fiber Spectroscopic Telescope. 展开更多
关键词 instrumentation:adaptive optics instrumentation:spectrographs proper motions reference systems
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Fine-grained grid computing model for Wi-Fi indoor localization in complex environments
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作者 Yan Liang Song Chen +1 位作者 Xin Dong Tu Liu 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第1期42-52,共11页
The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor localization.However,the construction of the fingerprint database is quite time-consuming.Especially when the posi... The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor localization.However,the construction of the fingerprint database is quite time-consuming.Especially when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is difficult.An appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)applications.In this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization accuracy.Reference points(RPs)are generated in the grid by the FGGC model.Then,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex environments.As a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous methods.The proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy simultaneously.The mean error of the proposed model is 0.36 m,far lower than that of previous approaches.Thus,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor localization.It also shows high-accuracy performance with a fast running speed even under a large-size grid.The results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue. 展开更多
关键词 Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)
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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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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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