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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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Alanine aminotransferase predicts incident steatotic liver disease of metabolic etiology: Long life to the old biomarker!
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作者 Amedeo Lonardo 《World Journal of Gastroenterology》 SCIE CAS 2024年第24期3016-3021,共6页
Alanine aminotransferase(ALT)serum levels increase because of hepatocellular damage.Metabolic dysfunction-associated fatty liver disease(MAFLD),which identifies steatotic liver disease(SLD)associated with≥2 metabolic... Alanine aminotransferase(ALT)serum levels increase because of hepatocellular damage.Metabolic dysfunction-associated fatty liver disease(MAFLD),which identifies steatotic liver disease(SLD)associated with≥2 metabolic abnormalities,has prominent sexual differences.The Metabolic Syndrome defines a cluster comprising abdominal obesity,altered glucose metabolism,dyslipidemia,and hypertension.Male sex,body mass index,glucose,lipids,ferritin,hypertension,and age independently predict ALT levels among blood donors.Over the last few decades,the reference range of ALT levels has been animatedly debated owing to attempts to update sex-specific reference ranges.With this backset,Chen et al have recently published a study which has two main findings.First,>80%of indi-viduals with MAFLD had normal ALT levels.Second,there was a linear increa-sing trend in the association between cumulative excess high-normal ALT levels and the rate of incident MAFLD.This study has biologically credible findings.However,it inaccurately considered sex differences in the MAFLD arena.Therefore,future studies on SLD owing to metabolic dysfunction should adopt locally determined and prospectively validated reference ranges of ALT and carefully consider sex differences in liver enzymes and MAFLD pathobiology. 展开更多
关键词 Alanine aminotransferase BIOMARKER History of medicine Metabolic dysfunction-associated fatty liver disease METABOLISM Nonalcoholic fatty liver disease reference range Sex differences Steatotic liver disease
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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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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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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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Maternal Deaths after Obstetrical Referral and/or Evacuation to the Obstetrics Gynecology Clinic of the Sylvanus Olympio University Hospital Center, Togo
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作者 Ameyo Ayoko Ketevi Bidilukinu Katende +5 位作者 Akila Bassowa Komlan Alessi Andele Baguilane Douaguibe Dédé Régine Diane Ajavon Abdoul Samadou Aboubakari Koffi Akpadza 《Advances in Reproductive Sciences》 CAS 2023年第2期37-45,共9页
Introduction: Maternal death or maternal mortality is “the death of a woman occurring during pregnancy or within 42 days of termination, regardless of duration or location, for any specific cause or aggravated b... Introduction: Maternal death or maternal mortality is “the death of a woman occurring during pregnancy or within 42 days of termination, regardless of duration or location, for any specific cause or aggravated by pregnancy or its management, but neither accidental nor fortuitous. Methods: This was a descriptive and analytical cross-sectional study carried out from January 1<sup>st</sup>, 2021 to April 30<sup>th</sup>, 2022 at the Obstetrics Gynecology Clinic of the Sylvanus Olympio University Hospital Center (SOUHC). Results: we noted 86 cases of maternal deaths after referral/evacuation i.e. a maternal mortality rate hospital of 555 maternal deaths per 100,000 LB. The average age of the patients was 31.1 ± 6.3 years with extremes of 15 and 45 years. In 33.7% of cases our patients were resellers. Multiparas represented 33.7% of the sample, they had performed less than three antenatal consultations. Postpartum hemorrhage was the reference reason in 33.7%. In 74.4% of cases, the patients referred had arrived by taxi. In 87.9% of cases, the patients had died of direct obstetric causes. Immediate postpartum hemorrhage accounted for 44.6% of cases and anemia, 36.4%. There is a statistically significant association between the availability of blood product and the avoidability of maternal death after obstetrical referral and/or evacuation (p value = 0.0188  0.05). Conclusion: Determining responsibility for maternal death is not always easy. There is an urgent need to strengthen the policy of reducing maternal mortality in Togo. This remains possible by developing communication strategies and a solid referral/counter-referral system. 展开更多
关键词 Maternal Death referENCE Counter reference toGO
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Capacity Development of National Reference Centers (NRC) to Face the Challenges of Emerging Infections in Côte d’Ivoire
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作者 Diané Kouao Maxime Adjogoua Edgard Valery +8 位作者 Coulibaly Ngolo Antoine Marie-David Kadjo A. Hervé N’guessan Kouassi Raymond Sylla Yahaya Anne Blessa Jean Claude Beourou Sylvain Guessennd-Kouadio Aya Nathalie Dosso Mireille Tiembré Issiaka 《Open Journal of Internal Medicine》 2023年第3期181-208,共28页
Background: Some national and international strategies for the detection and prevention of emerging infectious diseases have been established across sectors. The capacity to carry out these tasks varies from country t... Background: Some national and international strategies for the detection and prevention of emerging infectious diseases have been established across sectors. The capacity to carry out these tasks varies from country to country, and that remains largely undervalued. The Pasteur Institute of C?te d’Ivoire has created and implemented the capacity of national reference centers to fight against emerging and other infectious diseases. Objective: Show on the one hand the strategies used to develop the National Reference Centers and the IPCI and on the other hand the results obtained by performing these strategies. Method: Datas collection by documentary analysis (published scientific articles and grey literature) was done on Google Scholar, PUBMED and institutional reference documents. The documentary research was carried out to have a better understanding of strategies used to create and develop the NRCs in microbiology of communicable diseases. Results: Seven integrated strategies were launched: 1-training and workforce development;2-investigation of epidemics or public health events;3-strengthening laboratory epidemiological research;4-strengthening surveillance systems;5-improving communication with partners and stakeholders;6-building national and international collaborations;and 7-strengthening technical and technological platforms. In two decades, the number of researchers has risen from 10 in 2004 to ninety (90) in 2021, with 12 senior researchers and 32 junior researchers. A number of health service staff had attended a qualifying training course, 27 investigations into outbreaks and other public health events had been carried out, 18 short-term research projects had been launched, major surveillance programs and epidemiological research efforts on vector-borne, food-borne and nosocomial infections had begun, and several scientific manuscripts had been published or were edited in the writting press. Conclusion: The Ivorian experience shows that, with concerted effort, considerable progress can be made in the development and implementation of an infectious disease control program. 展开更多
关键词 EVALUATION Communicable Diseases National reference Centerorlaboratorie Capacity Development Côte d’Ivoire
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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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The System of Reference and Lexical Cohesion in Newspaper-An Example of Analyzing "Beijing and Shanghai in Race to Attract Top Foreign Talents"
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作者 蔡丹 《英语广场(学术研究)》 2012年第2期35-38,共4页
Discourse analysis is gaining its prominence in teaching reading. The paper presents an example of analyzing the system of reference and lexical cohesion of a news report. It demonstrates how to involve discourse anal... Discourse analysis is gaining its prominence in teaching reading. The paper presents an example of analyzing the system of reference and lexical cohesion of a news report. It demonstrates how to involve discourse analysis into the teaching of newspaper reading in order to make students get a clear framework of reference and lexical cohesion in a functional-grammar-conscious manner. 展开更多
关键词 referENCE lexical cohesion NEWSPAPER
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The China Seismological Reference Model project 被引量:3
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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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Correction to:Bottomonium suppression in heavy‑ion collisions and the in‑medium strong force 被引量:1
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作者 Ralf Rapp 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第5期85-85,共1页
Correction to:NUCL SCI TECH(2023)34:63 https://doi.org/10.1007/s41365-023-01213-3 While typesetting,reference[16]in the list has not been properly placed in the proof.The orders of the references[13-16]were mistaken b... Correction to:NUCL SCI TECH(2023)34:63 https://doi.org/10.1007/s41365-023-01213-3 While typesetting,reference[16]in the list has not been properly placed in the proof.The orders of the references[13-16]were mistaken by the production.The correct order of the references is. 展开更多
关键词 PROPERLY ORDERS referENCES
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Use of a Land Surface Model to Evaluate the Observed Soil Moisture of Grassland at the Tongyu Reference Site 被引量:9
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作者 丹利 季劲钧 刘辉志 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1073-1084,共12页
A land surface model driven by the continuous three-year observed meteorological data with a time interval of 30 minutes at the Tongyu station, a reference site of the Coordinated Enhanced Observing Period (CEOP), w... A land surface model driven by the continuous three-year observed meteorological data with a time interval of 30 minutes at the Tongyu station, a reference site of the Coordinated Enhanced Observing Period (CEOP), was used to evaluate the observation bias of soil moisture (SM) data and analyze the variation of SM at different time scales. The saline-alkaline soil of the grassland at the Tongyu site makes the measured SM too high, especially in boreal summer of 2003-05. The simulated annual mean SM has the lowest value in 2004 and its three-year variation corresponds to the change of precipitation, whereas the observation shows the increasing trend from 2003 to 2005. Compared to the variation range between -60% and 40% for the anomaly percentage of the simulated daily mean SM during May-October of 2004, the measured data show the higher values more than 40%. The magnitude of the variation trend of the observed daily mean SM in 2003 and 2005 is generally consistent with the simulation. The largest deficiency for the soil moisture observation of the grassland is the overestimated value in the drought year with less precipitation. The simulated monthly mean SM has the lowest value in March due to the large contribution of evaporation relative to precipitation and this phenomenon can not be reproduced in the observation. 展开更多
关键词 soil moisture variation trend tongyu reference site AVIM data evaluation
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A new free-hand pedicle screw placement technique with reference to the supraspinal ligament 被引量:7
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作者 Juming Li Hong Zhao +7 位作者 Hao Xie Lipeng Yu Jifu Wei Min Zong Feng Chen Ziqiang Zhu Ning Zhang Xiaojian Cao 《The Journal of Biomedical Research》 CAS 2014年第1期64-70,共7页
We sought to compare the safety and accuracy of a new free-hand pedicle screw placement technique to that of the conventional technique. One hundred fifty-three consecutive adult patients with simple fracture in the t... We sought to compare the safety and accuracy of a new free-hand pedicle screw placement technique to that of the conventional technique. One hundred fifty-three consecutive adult patients with simple fracture in the tho- racic or/and lumbar spine were alternately assigned to either the new free-hand or the conventional group. In the new free-hand technique group, preoperative computerized tomography (CT) images were used to calculate the targeted medial-lateral angle of each pedicle trajectory and the pedicle screw was inserted perpendicular to the corresponding supraspinal ligament. In the conventional technique group, the medial-lateral and cranial-caudal angle of each pedicle trajectory was determined by intraoperatively under fluoroscopic guidance. The accuracy rate of pedicle screw placement, the time of intraoperative fluoroscopy, the operating time and the amount of blood loss during operation were respectively compared. All screws were analyzed by using intraoperative ra- diographs, intraoperative triggered electromyography (EMG) monitoring data, postoperative CT data and clinical outcomes. The accuracy rate of pedicle screw placement in the new free-hand technique group and the conven- tional technique group was 96.3% and 94.2% (P 〈 0.05), respectively. The intraoperative fluoroscopy time of the new technique group was less than that of the conventional technique group (5.37 seconds vs. 8.79 seconds, P 〈 0.05). However, there was no statistical difference in the operating time and the amount of blood loss during op- eration (P 〉 0.05). Pedicle screw placement with the free-hand technique which keeps the screw perpendicular to the supraspinal ligament is an accurate, reliable and safe technique to treat simple fracture in the thoracic or lum- bar spine. 展开更多
关键词 spine fracture pedicle screw placement radiation exposure supraspinal ligament anatomy reference
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Identification of optimal reference genes in golden Syrian hamster with ethanol-and palmitoleic acid-induced acute pancreatitis using quantitative real-time polymerase chain reaction
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作者 Jinxin Miao Le Kang +7 位作者 Tianfeng Lan Jianyao Wang Siqing Wu Yifan Jia Xia Xue Haoran Guo Pengju Wang Yan Li 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第6期609-618,共10页
Background:Acute pancreatitis(AP)is a severe disorder that leads to high morbidity and mortality.Appropriate reference genes are important for gene analysis in AP.This study sought to study the expression stability of... Background:Acute pancreatitis(AP)is a severe disorder that leads to high morbidity and mortality.Appropriate reference genes are important for gene analysis in AP.This study sought to study the expression stability of several reference genes in the golden Syrian hamster,a model of AP.Methods:AP was induced in golden Syrian hamster by intraperitoneal injection of ethanol(1.35 g/kg)and palmitoleic acid(2 mg/kg).The expression of candidate genes,including Actb,Gapdh,Eef2,Ywhaz,Rps18,Hprt1,Tubb,Rpl13a,Nono,and B2m,in hamster pancreas at different time points(1,3,6,9,and 24 h)posttreatment was analyzed using quantitative polymerase chain reaction.The expression stability of these genes was calculated using Best Keeper,Comprehensive Delta CT,Norm Finder,and ge Norm algorithms and Ref Finder software.Results:Our results show that the expression of these reference genes fluctuated during AP,of which Ywhaz and Gapdh were the most stable genes,whereas Tubb,Eef2,and Actb were the least stable genes.Furthermore,these genes were used to normalize the expression of TNF-αmessenger ribonucleic acid in inflamed pancreas.Conclusions:In conclusion,Ywhaz and Gapdh were suitable reference genes for gene expression analysis in AP induced in Syrian hamster. 展开更多
关键词 acute pancreatitis reference genes Syrian hamster TNF-Α
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Evaluation of reference genes for quantitative real-time PCR analysis of gene expression during early development processes of the tongue sole(Cynoglossus semilaevis) 被引量:3
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作者 MA Qian ZHUANG Zhimeng +2 位作者 FENG Wenrong LIU Shufang TANG Qisheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第10期90-97,共8页
Differential expression of genes is crucial to growth and development of fish. To select the appropriate genes for gene normalization during Cynoglossus semilaevis early developmental process, eight candidate referenc... Differential expression of genes is crucial to growth and development of fish. To select the appropriate genes for gene normalization during Cynoglossus semilaevis early developmental process, eight candidate reference genes (ACTB, B2M, EF1A, GADPH, RPL7, TUBA, UBCE and 18S) were tested for their adequacy by using quantitative real-time PCR. The results showed that the expression of all the examined genes exhibited tissue dependent variations in the mature C. semilaevis. EFIA was listed as the most stable reference among the 14 tissues by RefFinder. Furthermore, the recommended comprehensive ranking of the stability determined by RefFinder showed that 18S was the most stable gene during the early developmental stages (from oosphere to 90 days old) in this study. However, when divided the Ct value data of the above mentioned early developmental stages into two separate periods (embryo and post-hatching periods), TUBA and 18S represented the most stable references of these two developmental periods, respectively. Consequently, the reference gene should be carefully and accurately chosen even for studies of the same species at various developmental processes. The relevant data may help in selecting appropriate reference genes for mRNA expression analysis, and is of great value in the studies of fish growth and development. 展开更多
关键词 quantitative real-time PCR reference gene early development Cynoglossus semilaevis
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RT-qPCR normalization of reference genes in different lifehistory stages of Gracilaria vermiculophylla(Rhodophyta)
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作者 Yingyue ZHANG Jinxin YANG +2 位作者 Ze YANG Cong QI Di XU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第5期1910-1917,共8页
The quantitative realtime polymerase chain reaction(RT-qPCR)is a powerful and sensitive method to measure expression of targeted gene but it highly relies on the use of suitable reference genes for data normalization.... The quantitative realtime polymerase chain reaction(RT-qPCR)is a powerful and sensitive method to measure expression of targeted gene but it highly relies on the use of suitable reference genes for data normalization.We evaluated the expressions of 8 housekeeping genes:18S ribosomal rDNA(18S rDNA),28S ribosomal r DNA(28S rDNA),rubisco large subunit(rbc-L),β-actin(ACT),glyceraldehyde-3-phosphate dehydrogenase(GAPDH),elongation factor 1(EF1),β-tubulin(Tub B),and P-phycoerythrin B(PEB),to select the suitable reference genes for different life-history stages(tetrasporophyte,carposporophyte,and male/female gametophyte)of Gracilaria vermiculophylla by absolute quantitative method.Softwares geNorm and BestKeeper were used to verify the results acquired from copy number analysis.Results show that the expression of identified reference genes varied in comparing groups composed of different type of life stages.It is suggested that 18S rDNA and TubB could be used for highly complex samples composed of mixed ploidy and phases.18S rDNA and 28S rDNA were also preferred for using among the matured isomorphic samples.But for samples with different maturities,TubB and ACT were recommended for tetrasporophytes and gametophytes respectively. 展开更多
关键词 reference gene Gracilaria vermiculophylla life-history stage quantitative real-time polymerase chain reaction(RT-qPCR) red algae
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Responses of vegetation yield to precipitation and reference evapotranspiration in a desert steppe in Inner Mongolia,China
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作者 LI Hongfang WANG Jian +2 位作者 LIU Hu MIAO Henglu LIU Jianfeng 《Journal of Arid Land》 SCIE CSCD 2023年第4期477-490,共14页
Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the charact... Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the characteristics of drought events.Studying precipitation,reference evapotranspiration(ET_(0)),and vegetation yield can derive information to help conserve water resources in grassland ecosystems in arid and semi-arid regions.In this study,the interactions of precipitation,ET_(0),and vegetation yield in Darhan Muminggan Joint Banner(DMJB),a desert steppe in Inner Mongolia Autonomous Region,China were explored using two-dimensional(2D)and three-dimensional(3D)joint distribution models.Three types of Copula functions were applied to quantitatively analyze the joint distribution probability of different combinations of precipitation,ET_(0),and vegetation yield.For the precipitation–ET_(0)dry–wet type,the 2D joint distribution probability with precipitation≤245.69 mm/a or ET_(0)≥959.20 mm/a in DMJB was approximately 0.60,while the joint distribution probability with precipitation≤245.69 mm/a and ET_(0)≥959.20 mm/a was approximately 0.20.Correspondingly,the joint return period that at least one of the two events(precipitation was dry or ET_(0)was wet)occurred was 2 a,and the co-occurrence return period that both events(precipitation was dry and ET_(0)was wet)occurred was 5 a.Under this condition,the interval between dry and wet events would be short,the water supply and demand were unbalanced,and the water demand of vegetation would not be met.In addition,when precipitation remained stable and ET_(0)increased,the 3D joint distribution probability that vegetation yield would decrease due to water shortage in the precipitation–ET_(0)dry–wet years could reach up to 0.60–0.70.In future work,irrigation activities and water allocation criteria need to be implemented to increase vegetation yield and the safety of water resources in the desert steppe of Inner Mongolia. 展开更多
关键词 PRECIPITATION reference evapotranspiration vegetation yield Copula functions desert steppe dry and wet events Inner Mongolia
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Selection of the appropriate reference genes by quantitative real-time PCR in leopard coral groupers Plectropomus leopardus
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作者 Han ZHANG Haoran YANG +5 位作者 Pengsuo LI Na ZHAO Xiaojuan CHEN Yongcan ZHOU Zhenjie CAO Yun SUN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期1084-1099,共16页
Leopard coral groupers(Plectropomus leopardus),commercially bred in South China,are a significant economical fish species.In this study,by means of quantitative real-time PCR(qRT-PCR)technology,we assessed the stabili... Leopard coral groupers(Plectropomus leopardus),commercially bred in South China,are a significant economical fish species.In this study,by means of quantitative real-time PCR(qRT-PCR)technology,we assessed the stability of six common reference genes expression and selected the appropriate reference genes in leopard coral groupers with or without Vibrio harveyi stimulation at different time points.These data produced by qRT-PCR was handled via the geNorm,NormFinder,and BestKeeper software.The results revealed all the examined reference genes had manifest tissue-specific expression in different tissues.Prior to V.harveyi stimulation,RPL13 gene was the appropriate reference gene among eleven tissue types(blood,spleen,hepatopancreas,kidney,stomach,gill,heart,skin,muscle,intestine,brain)in leopard coral groupers.Under V.harveyi stimulation,the most reliable reference genes varied from tissue to tissue and were closely hinged upon different time points.At 6-h post-bacterial injection,the appropriate reference genes in hepatopancreas,spleen,kidney,and gill were Actin,B2M,UBCE,and Actin,respectively.At 9-and 12-h post-bacterial injection,the appropriate reference genes in hepatopancreas,spleen,kidney,and gill were RPL13,Actin,Actin,and Actin,respectively.If one reference gene was preferable,RPL13,Actin,Actin,and Actin could be selected as the reference gene in hepatopancreas,spleen,kidney,and gill of leopard coral groupers after V.harveyi infection,respectively.Expression profiles of two target genes(IL-6 and NK-lysin)were used to further validate reliability of these selected appropriate candidates.This study will lay a solid foundation for the future research on qRTPCR analysis of gene expression in leopard coral groupers. 展开更多
关键词 Plectropomus leopardus reference genes Vibrio harveyi stimulation
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Selection of Stable Reference Genes for Quantitative Real-Time PCR on Herbaceous Peony (Paeonia lactiflora Pall.) in Response to Drought Stress
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作者 Zhipeng Sheng Yuting Luan +2 位作者 Cong Xu Jun Tao Daqiu Zhao 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第3期801-814,共14页
Herbaceous peony(Paeonia lactiflora Pall.),as a high-end cut flower in the international market,has high ornamental and medicinal values.But in Northern China,drought is a major environmental factor influencing the gr... Herbaceous peony(Paeonia lactiflora Pall.),as a high-end cut flower in the international market,has high ornamental and medicinal values.But in Northern China,drought is a major environmental factor influencing the growth and development of P.lactiflora.Quantitative real-time polymerase chain reaction(qRT-PCR)can evaluate gene expression levels under different stress conditions,and stable internal reference is the key for qRT-PCR.At present,there is no systematic screening of internal reference for correcting gene expressions of P.lactiflora in response to drought stress.In this study,10 candidate genes[ubiquitin(UBQ2),UBQ1,elongation factor 1-α(EF-1α),Histidine(His),eukaryotic initiation factor(eIF),tubulin(TUB),actin(ACT),UBQ3,ACT2,RNA polymerase II(RNA Pol II)]were chosen,and 4 analysis methods were used to compare the stabilities for these 10 genes coping with drought stress.Due to the difference of operation methods,the results of different analysis were distinct,and the final comprehensive analysis indicated that EF-1αwas a relatively stable internal reference gene for P.lactiflora under drought stress.Also,UBQ1 and UBQ2 were the best reference gene combination according to GeNorm analysis.This study will lay a foundation for screening the key genes of P.lactiflora in response to drought stress. 展开更多
关键词 Herbaceous peony QRT-PCR reference gene drought stress
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Stochastic Investigations for the Fractional Vector-Host Diseased Based Saturated Function of Treatment Model
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作者 Thongchai Botmart Qusain Hiader +2 位作者 Zulqurnain Sabir Muhammad Asif Zahoor Raja Wajaree Weera 《Computers, Materials & Continua》 SCIE EI 2023年第1期559-573,共15页
The goal of this research is to introduce the simulation studies of the vector-host disease nonlinear system(VHDNS)along with the numerical treatment of artificial neural networks(ANNs)techniques supported by Levenber... The goal of this research is to introduce the simulation studies of the vector-host disease nonlinear system(VHDNS)along with the numerical treatment of artificial neural networks(ANNs)techniques supported by Levenberg-Marquardt backpropagation(LMQBP),known as ANNs-LMQBP.This mechanism is physically appropriate,where the number of infected people is increasing along with the limited health services.Furthermore,the biological effects have fadingmemories and exhibit transition behavior.Initially,the model is developed by considering the two and three categories for the humans and the vector species.The VHDNS is constructed with five classes,susceptible humans Sh(t),infected humans Ih(t),recovered humans Rh(t),infected vectors Iv(t),and susceptible vector Sv(t)based system of the fractional-order nonlinear ordinary differential equations.To solve the number of variations of the VHDNS,the numerical simulations are performed using the stochastic ANNs-LMQBP.The achieved numerical solutions for solving the VHDNS using the stochastic ANNs-LMQBP have been described for training,verifying,and testing data to decrease the mean square error(MSE).An extensive analysis is provided using the correlation studies,MSE,error histograms(EHs),state transitions(STs),and regression to observe the accuracy,efficiency,expertise,and aptitude of the computing ANNs-LMQBP. 展开更多
关键词 Nonlinear mathematical vector host disease model fractional order levenberg marquardt backpropagation neural network reference database
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