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Multi-center investigation of breast reconstruction after mastectomy from Chinese Society of Breast Surgery:A survey based on 31 tertiary hospitals(CSBrS-004) 被引量:7
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作者 Feng Xu Chuqi Lei +4 位作者 Heng Cao Jun Liu Jie Li Hongchuan Jiang Chinese Society of Breast Surgery 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2021年第1期33-41,共9页
Objective:Multi-center data on the current status and trends of breast reconstruction after mastectomy in China are lacking.Herein,we conducted a cross-sectional survey to investigate the current clinical practice pat... Objective:Multi-center data on the current status and trends of breast reconstruction after mastectomy in China are lacking.Herein,we conducted a cross-sectional survey to investigate the current clinical practice pattern of postmastectomy breast reconstruction among Chinese female patients with breast cancer.Methods:A standardized questionnaire used to collect information on breast reconstruction among females diagnosed with breast cancer was distributed by 31 members of the Chinese Society of Breast Surgery between January 1,2018 and December 31,2018.Information was collected on tumor characteristics,treatment,mesh application,nipple-areola complex(NAC)preservation,postoperative complications,bilateral reconstruction,patient satisfaction and local recurrence.The overall rate of breast reconstruction was assessed,and the characteristics were compared across patient groups with different reconstruction approaches.Results:A total of 1,554 patients underwent breast reconstruction after total mastectomy,with a reconstruction rate of 9.6%.Among them,1,190 were implant-based,and 262 underwent autologous reconstructions,while 102 cases underwent a combination of both.Patients who underwent implant-based reconstruction were younger than those who received autologous reconstruction(40.1±4.6 vs.45.0±5.9,P=0.004).Compared to patients with autologous reconstruction,mesh application(25.5%vs.6.5%),NAC preservation(51.8%vs.40.5%)and reconstruction failure(1.8%vs.0)were more frequently reported among those with implant-based reconstruction.There was no significant difference in general satisfaction across three reconstruction approaches,though patients with autologous reconstruction reported the highest aesthetic satisfaction among the three groups(P=0.044).Conclusions:Implant-based breast reconstruction remains the dominant choice among patients,while autologous reconstruction was associated with higher aesthetic satisfaction.Our multi-center investigation based on the findings of the tertiary hospitals of Chinese Society of Breast Surgery may guide a future series of clinical studies on breast reconstruction in China. 展开更多
关键词 Breast cancer MASTECTOMY breast reconstruction questionnaire survey patient satisfaction
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Theoretical study of(e,2e) triple differential cross section of 1b3g orbital of ethylene by vibrational multi-center distorted-wave method
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作者 王振鹏 宫毛毛 +2 位作者 李星宇 张松斌 陈向军 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期306-312,共7页
The vibrational motions are usually neglected when calculating(e,2e) triple differential cross sections(TDCSs) of molecules. Here, multi-center distorted-wave method(MCDW) has been modified by including molecular vibr... The vibrational motions are usually neglected when calculating(e,2e) triple differential cross sections(TDCSs) of molecules. Here, multi-center distorted-wave method(MCDW) has been modified by including molecular vibrations. This vibrational MCDW method is employed to calculate the TDCSs of 1b3gorbital of ethylene at low(100 eV) and medium(250 eV) incident electron energies in coplanar asymmetric kinematic condition. The results show that molecular vibrations significantly influence the angular distributions of the TDCSs, especially in the binary region along momentum transfer near the Bethe ridge. 展开更多
关键词 (e 2e) multi-center distorted-wave method(MCDW) vibrational effect
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Effect of a disposable endoscope precleaning kit in the cleaning procedure of gastrointestinal endoscope:A multi-center observational study
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作者 Yi-Fan Wang Yu Wu +10 位作者 Xiao-Wei Liu Jian-Guo Li Yan-Qiong Zhan Bin Liu Wen-Ling Fan Zi-Heng Peng Jin-Tao Xiao Bing-Bing Li Jian He Jun Yi Zhao-Xia Lu 《World Journal of Gastrointestinal Endoscopy》 2023年第12期705-714,共10页
BACKGROUND Precleaning is a key step in endoscopic reprocessing.AIM To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.METHODS Altogether,228 used ga... BACKGROUND Precleaning is a key step in endoscopic reprocessing.AIM To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.METHODS Altogether,228 used gastrointestinal endoscopes were selected from five high-volume endoscopy units and precleaned by a traditional precleaning bucket(group T)or a disposable endoscope bedside precleaning kit(group D).Each group was further subdivided based on the replacement frequency of the cleaning solution,which was replaced every time in subgroups T1 and D1 and every several times in subgroups Ts and Ds.The adenosine triphosphate(ATP)level and residual proteins were measured three times:Before and after precleaning and after manual cleaning.RESULTS After precleaning,the precleaning kit significantly reduced the ATP levels(P=0.034)and has a more stable ATP clearance rate than the traditional precleaning bucket.The precleaning kit also saved a quarter of the cost of enzymatic detergent used during the precleaning process.After manual cleaning,the ATP levels were also significantly lower in the precleaning kit group than in the traditional precleaning bucket group(P<0.05).Meanwhile,the number of uses of the cleaning solution(up to four times)has no significant impact on the cleaning effect(P>0.05).CONCLUSION Considering its economic cost and cleaning effect,the use of a disposable endoscope bedside precleaning kit can be an optimal option in the precleaning stage with the cleaning solution being replaced several times in the manual cleaning stage. 展开更多
关键词 Cleaning effect Economic cost ENDOSCOPE multi-center study Precleaning
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Basic Survey Scheduling for the Wide Field Survey Telescope(WFST)
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作者 Yan-Peng Chen Ji-An Jiang +5 位作者 Wen-Tao Luo Xian-Zhong Zheng Min Fang Chao Yang Yuan-Yu Hong Zong-Fei Lü 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期59-69,共11页
Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather cond... Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather conditions at the Lenghu site. The sky area is divided into rectangular regions, referred to as “tiles,” with a size of2°. 577 × 2°. 634 slightly smaller than the focal area of the mosaic CCDs. These tiles are continuously filled in annulars parallel to the equator. The brightness of the sky background, which varies with the moon phase and distance from the moon, plays a significant role in determining the accessible survey fields. Approximately 50connected tiles are grouped into one block for observation. To optimize the survey schedule, we perform simulations by taking into account the length of exposures, data readout, telescope slewing, and all relevant observing conditions. We utilize the Greedy Algorithm for scheduling optimization. Additionally, we propose a dedicated dithering pattern to cover the gaps between CCDs and the four corners of the mosaic CCD array, which are located outside of the 3° field of view. This dithering pattern helps to achieve relatively uniform exposure maps for the final survey outputs. 展开更多
关键词 telescopes surveys MOON
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Enhancing landslide hazards survey and management to reduce the loss of human lives and properties
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作者 Yong-shuang Zhang 《China Geology》 CAS CSCD 2024年第2期169-170,共2页
Landslides are pervasive geohazards that pose a serious threat to human lives,property,and crucial engineering constructions.Annually,landslides lead to tens of thousands of fatalities(see the paper of"List of ty... Landslides are pervasive geohazards that pose a serious threat to human lives,property,and crucial engineering constructions.Annually,landslides lead to tens of thousands of fatalities(see the paper of"List of typical catastrophic landslides from March 2004 to February 2024"in this issue,doi:10.31035/cg2024079)and cause economic damages amounting to billions of dollars around the world,as well as disrupting crucial infrastructures such as railways,highways。 展开更多
关键词 hazards survey DOLLAR
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Spatial structural characteristics of the Deda ancient landslide in the eastern Tibetan Plateau:Insights from Audio-frequency Magnetotellurics and the Microtremor Survey Method
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作者 Zhen-dong Qiu Chang-bao Guo +5 位作者 Yi-ying Zhang Zhi-hua Yang Rui-an Wu Yi-qiu Yan Wen-kai Chen Feng Jin 《China Geology》 CAS CSCD 2024年第2期188-202,共15页
It is of crucial importance to investigate the spatial structures of ancient landslides in the eastern Tibetan Plateau’s alpine canyons as they could provide valuable insights into the evolutionary history of the lan... It is of crucial importance to investigate the spatial structures of ancient landslides in the eastern Tibetan Plateau’s alpine canyons as they could provide valuable insights into the evolutionary history of the landslides and indicate the potential for future reactivation.This study examines the Deda ancient landslide,situated in the Chalong-ranbu fault zone,where creep deformation suggests a complex underground structure.By integrating remote sensing,field surveys,Audio-frequency Magnetotellurics(AMT),and Microtremor Survey Method(MSM)techniques,along with engineering geological drilling for validation,to uncover the landslide’s spatial feature s.The research indicates that a fault is developed in the upper part of the Deda ancient landslide,and the gully divides it into Deda landslide accumulation zoneⅠand Deda landslide accumulation zoneⅡin space.The distinctive geological characteristics detectable by MSM in the shallow subsurface and by AMT in deeper layers.The findings include the identification of two sliding zones in the Deda I landslide,the shallow sliding zone(DD-I-S1)depth is approximately 20 m,and the deep sliding zone(DD-I-S2)depth is 36.2-49.9 m.The sliding zone(DD-Ⅱ-S1)depth of the DedaⅡlandslide is 37.6-43.1 m.A novel MSM-based method for sliding zone identification is proposed,achieving less than 5%discrepancy in depth determination when compared with drilling data.These results provide a valuable reference for the spatial structural analysis of large-deepseated landslides in geologically complex regions like the eastern Tibetan Plateau. 展开更多
关键词 Ancient landslide Remote sensing Audio-frequency Magnetotellurics(AMT) Microtremor survey Method(MSM) Geological drilling engineering Spatial structure Tibetan Plateau Geological hazard survey engineering
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Survey on performance of vertical slot and nature-like fishways at Angu hydropower station, Southwest China
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作者 Jun-jian Sun Jia-yue Shi +2 位作者 Qi Zhang Xiao-tao Shi Jun-jun Tan 《Water Science and Engineering》 EI CAS CSCD 2024年第1期83-91,共9页
To restore dam-blocked natural fish migratory passages,a growing number of artificial fishways have been built in water conservancy and hydropower projects in China.The Angu hydropower station involved diverse importa... To restore dam-blocked natural fish migratory passages,a growing number of artificial fishways have been built in water conservancy and hydropower projects in China.The Angu hydropower station involved diverse important fish habitats in the lower reaches of the Daduhe River in Southwest China.Therefore,a vertical slot fishway(VSF)and a nature-like fishway(NLF)were built near the backwater area of the reservoir to connect the upstream and downstream habitats.Hydrodynamic and aquatic ecological surveys were conducted after the completion of the project to estimate the fish passing effect of the two fishways.The results indicated that both fishways were in effective operation and could maintain the desired hydrodynamic conditions and be used by several local fish species.During the survey,149 fish from 15 species and 111 fish from 17 species were captured by the traps in the VSF and NLF,respectively,while 1263 fish from 27 species were found in the downstream area.Some species captured in the VSF were not found in the NLF,and vice versa,which implied the different preferences of fish.Meanwhile,3789 signals including 2099 upward ones and 1690 downward ones were monitored with an ultrasonic fish detector at the inlet of the VSF.These findings revealed the characteristics of fish species observed in and near the fishways and provided valuable insights into the different fish passing capabilities of VSFandNLF. 展开更多
关键词 Vertical slot fishway Nature-like fishway Aguatic ecological survey Fishwaymonitoring Statistical analysis
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Diagnostic values of questionnaires of Convergence Insufficiency Symptom Survey and College of Optometrists Vision Development Quality of Life in the screening of convergence insufficiency
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作者 Ling Xiong Qian Chen Ye Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期904-908,共5页
AIM:To compare and analyse the diagnostic efficacy of the College of Optometrists Vision Development Quality of Life Questionnaire(COVD-QOL)and the Convergence Insufficiency Symptom Survey(CISS)in detecting convergenc... AIM:To compare and analyse the diagnostic efficacy of the College of Optometrists Vision Development Quality of Life Questionnaire(COVD-QOL)and the Convergence Insufficiency Symptom Survey(CISS)in detecting convergence insufficiency and to compare their diagnostic value in clinical applications.METHODS:Using the diagnostic test method,62 adult patients with convergence insufficiency(age:24.74±3.75y)and 62 normal participants(age:23.61±3.13y)who visited the Optometry Clinic of West China Hospital of Sichuan University from April 2021 to January 2023 were included.All subjects completed the CISS and COVD-QOL.Statistical analysis of the sensitivity and specificity of the CISS and COVD-QOL and comparison and joint experimental analysis of their diagnostic efficacy were performed.RESULTS:The sensitivity of the CISS and COVD-QOL for convergence insufficiency was 64.5%and 71.0%,respectively,while the specificity was 96.8%and 67.7%,respectively.Compared to the CISS alone,the combination of the CISS and COVD-QOL demonstrated lower sensitivity and specificity.The areas under the receiver operating characteristic curve of CISS,COVD-QOL and CISS combined with COVD-QOL were 0.806,0.694 and 0.782,respectively.CONCLUSION:Considering the low sensitivity of the CISS and the low specificity of the COVD-QOL,it is recommended to supplement these questionnaires with other screening tests for the detection of convergence insufficiency. 展开更多
关键词 convergence insufficiency symptom survey College of Optometrists Vision Development Quality of Life Questionnaire convergence insufficiency ASTHENOPIA
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油茶象甲Curculio chinensis基因组Survey测序分析
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作者 张丽 吴佳茜 +2 位作者 曾萝琦 刘惠 汤小宇 《中国农学通报》 2024年第17期135-141,共7页
油茶象甲Curculio chinensis Chevrolat是危害中国特有木本油料树种——油茶的专性蛀果害虫,也是中国林业危险性有害生物之一,在中国不同油茶产区均有分布,对油茶的为害呈加重趋势。为了深入研究其遗传基础和寄主适应性,确定适合鞘翅目... 油茶象甲Curculio chinensis Chevrolat是危害中国特有木本油料树种——油茶的专性蛀果害虫,也是中国林业危险性有害生物之一,在中国不同油茶产区均有分布,对油茶的为害呈加重趋势。为了深入研究其遗传基础和寄主适应性,确定适合鞘翅目象甲科基因组测序研究策略,首先采取Survey测序,之后做深度基因组测序和大规模种群测序。研究采用二代高通量测序技术(MGISEQ-2000),测定了油茶象甲基因组大小,并估计该物种基因组的杂合度、重复率和GC含量。结果显示:油茶象甲基因组大小约为1356.82 Mb,测序深度达到50×;K-mer分析油茶象甲基因组虽然具有杂合峰,但杂合率较低,为1.20%;基因组重复序列含量约为77%。该研究结果对于揭示油茶象甲适应性进化具有重要意义,可为后续构建完整基因组和多种群基因组测序提供策略选择依据。 展开更多
关键词 油茶象甲 鞘翅目 survey测序 杂合率 GC含量
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Functional Confirmation Using a Medical X-Ray System of a Semiconductor Survey Meter
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作者 Katsunao Suzuki Toru Negishi +2 位作者 Yoh Kato Yasuhisa Kono Michiharu Sekimoto 《Open Journal of Radiology》 2024年第1期1-13,共13页
In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate ... In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate the time constant of a semiconductor survey meter and confirm the meter’s function. An additional filter was attached to the medical X-ray system to satisfy the standards of N-60 to N-120, more copper plates were added as needed, and the first and second half-value layers were calculated to enable comparisons of the facility’s X-ray system quality with the N-60 to N-120 quality values. Next, we used a medical X-ray system to measure the leakage dose and calculate the time constant of the survey meter. The functionality of the meter was then checked and compared with the energy characteristics of the meter. The experimental results showed that it was possible to use a medical X-ray system to reproduce the N-60 to N-120 radiation quality values and to calculate the time constant from the measured results, assuming actual leakage dosimetry for that radiation quality. We also found that the calibration factor was equivalent to that of the energy characteristics of the survey meter. 展开更多
关键词 Semiconductor survey Meter Functional Confirmation Medical X-Ray System Calibration Factor Time Constant
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Environmental Impact Assessment Follow-Up of Seismic Survey Offshore Activities in Brazil
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作者 Fontes Nuno Eduardo Paulo Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期141-155,共15页
Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest f... Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest from scientists and practitioners, though it is recognized as one of the weakest points of EIA systems globally. Also, EIA follow-up is influenced by the context, mainly in terms of the types of projects or activities and their related impacts on the environment. Therefore, the present paper is focused on the investigation of the follow-up stage applied to the activity of seismic survey coupled with offshore oil & gas exploitation in Brazil. Research was based on a qualitative approach that included document analysis and semi-structured interviews with analysts involved in EIA processes, and sought to generate evidence of effectiveness of the EIA follow-up as conducted by the Federal Environment Agency (Ibama) in order to situate the practice of follow-up in the broader context of international best practice principles. Based on the findings, it was concluded that, due to the peculiarities of offshore seismic survey, it is necessary to promote adaptations in the procedures for monitoring impacts in order to ensure proper alignment with the principles and conceptual foundations that guide EIA practice. Specifically, the timing of the execution of the activity imposes challenges for its integration into the “conventional” cycle that has guided the monitoring of the impacts in the EIA of projects. 展开更多
关键词 Environmental Impact Assessment Follow-Up Follow-Up Effectiveness Oil and Gas Offshore Seismic survey
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黄鲫的全基因组survey分析与微卫星分布特征
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作者 郑思旭 陈诗逸 +5 位作者 梁旭东 王云鹏 沈豪迪 黄文化 柳意樊 刘炳舰 《浙江海洋大学学报(自然科学版)》 CAS 2024年第2期93-100,共8页
对黄鲫进行了全基因组测序,并进行了survey分析和微卫星特征研究,旨在评估其基因组基本信息并为进一步研究该物种的遗传多样性和进化提供重要信息。研究表明,黄鲫基因组大小约为815Mb,重复序列比例为39.69%,杂合率为1.77%;通过初步组装... 对黄鲫进行了全基因组测序,并进行了survey分析和微卫星特征研究,旨在评估其基因组基本信息并为进一步研究该物种的遗传多样性和进化提供重要信息。研究表明,黄鲫基因组大小约为815Mb,重复序列比例为39.69%,杂合率为1.77%;通过初步组装,得到的ContigN50为35836bp,ScaffoldN50为107605bp。此外,在全基因组范围内,检测出了14.562379个微卫星位点,相对丰度约1713个·Mb^(-1);其中,二碱基重复最常见(90.64%),其次为单碱基重复(5.52%),6碱基重复较少(0.24%)。微卫星重复拷贝数主要分布在6~15次之间,AC/GT和AG/CT是最常见的2碱基重复类型。这些研究结果为黄鲫的遗传学及进化生物学研究提供了重要的信息,并且为黄鲫的遗传多样性保护提供了有用的分子标记。 展开更多
关键词 黄鲫 高通量测序 全基因组survey 微卫星标记
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Analysis of GPS Technology in Surveying and Mapping Engineering Technology
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作者 Hanyu Zhao 《Journal of World Architecture》 2024年第2期84-89,共6页
With the rapid advancement of digital and information technology,global positioning system(GPS)technology has seen increasing utilization in surveying and mapping engineering,extending its application across land,ocea... With the rapid advancement of digital and information technology,global positioning system(GPS)technology has seen increasing utilization in surveying and mapping engineering,extending its application across land,ocean,and various other domains.By analyzing the technical means of GPS in surveying and mapping engineering,understanding the characteristics and key technologies in different application environments,and exploring the application process and key technical means,accurate control can be effectively realized.Based on this,this paper mainly analyzes the specific application of GPS technology in surveying and mapping engineering technology for reference. 展开更多
关键词 surveying and mapping engineering technology GPS technology
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黑壳楠染色体核型分析及基因组Survey预测
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作者 逯久幸 刘燕 +3 位作者 许朵朵 陈鹏 李永华 刘红利 《河南农业大学学报》 CAS CSCD 2023年第6期967-974,共8页
【目的】明确黑壳楠(Lindera megaphylla)染色体形态结构特征和基因组基本信息。【方法】以野生黑壳楠为材料,采用荧光原位杂交法,对染色体进行核型分析,并通过基因组survey预测了黑壳楠基因组的基本信息。【结果】黑壳楠染色体数目为2n... 【目的】明确黑壳楠(Lindera megaphylla)染色体形态结构特征和基因组基本信息。【方法】以野生黑壳楠为材料,采用荧光原位杂交法,对染色体进行核型分析,并通过基因组survey预测了黑壳楠基因组的基本信息。【结果】黑壳楠染色体数目为2n=24,核型公式为2n=2X=24=18m(2SAT)+6sm,9号染色体存在1对随体,属于2B型染色体。染色体组绝对长度变异范围为2.92~5.83,相对长度的变化范围为5.33%~11.11%,核型不对称系数为59.49%。研究还发现,存在1对5S rDNA杂交位点和1对18S rDNA杂交位点,分别位于5号和9号染色体。18S rDNA杂交位点2个杂交信号位置相同、强度近似。基因组survey结果显示,黑壳楠基因大小为1.38 Gb,杂合率为0.8%,重复序列比例为70%。【结论】黑壳楠为2倍体,染色体数目为24条,核型相对对称。黑壳楠在樟科的进化中属于较为原始的物种,且染色体未发生重组、变异或者种内杂交等现象。黑壳楠为大基因组,杂合率较高,重复序列多的物种。 展开更多
关键词 黑壳楠 核型分析 荧光原位杂交 基因组survey
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Probing the structure of multi-center molecules with odd–even high harmonics 被引量:3
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作者 苏宁 于术娟 +2 位作者 李卫艳 杨世平 陈彦军 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期274-280,共7页
We study high-order harmonic generation(HHG) from multi-center asymmetric linear molecules numerically and analytically. Our simulations show that odd and even HHG spectra of the asymmetric multi-center system respo... We study high-order harmonic generation(HHG) from multi-center asymmetric linear molecules numerically and analytically. Our simulations show that odd and even HHG spectra of the asymmetric multi-center system respond differently to the change of the molecular structure. Specifically, when the internuclear distances between these nuclei of the molecule have a small change, the odd spectra usually do not change basically, but the even spectra differ remarkably. Based on this phenomenon, a simple procedure is proposed to probe the positions of these nuclei with odd–even HHG. Our results shed light on attosecond probing of the structure of multi-center molecules using HHG. 展开更多
关键词 odd-even harmonics multi-center asymmetric molecules molecular structure
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Minimum MSE Weights of Adjusted Summary Estimator of Risk Difference in Multi-Center Studies 被引量:1
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作者 Chukiat Viwatwongkasem Jirawan Jitthavech +1 位作者 Dankmar Bohning Vichit Lorchirachoonkul 《Open Journal of Statistics》 2012年第1期48-59,共12页
The simple adjusted estimator of risk difference in each center is easy constructed by adding a value c on the number of successes and on the number of failures in each arm of the proportion estimator. Assessing a tre... The simple adjusted estimator of risk difference in each center is easy constructed by adding a value c on the number of successes and on the number of failures in each arm of the proportion estimator. Assessing a treatment effect in multi-center studies, we propose minimum MSE (mean square error) weights of an adjusted summary estimate of risk difference under the assumption of a constant of common risk difference over all centers. To evaluate the performance of the proposed weights, we compare not only in terms of estimation based on bias, variance, and MSE with two other conventional weights, such as the Cochran-Mantel-Haenszel weights and the inverse variance (weighted least square) weights, but also we compare the potential tests based on the type I error probability and the power of test in a variety of situations. The results illustrate that the proposed weights in terms of point estimation and hypothesis testing perform well and should be recommended to use as an alternative choice. Finally, two applications are illustrated for the practical use. 展开更多
关键词 Minimum MSE WEIGHTS Optimal WEIGHTS Cochran-Mantel-Haenszel WEIGHTS Inverse Variance WEIGHTS multi-center STUDIES Risk Difference
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基于基因组survey的横带髭鲷(Hapalogenys analis)微卫星位点筛选与特征分析
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作者 刘焘 陈冰洁 +4 位作者 史会来 平洪领 张涛 瞿印权 高天翔 《海洋与湖沼》 CAS CSCD 北大核心 2023年第3期848-855,共8页
探究横带髭鲷(Hapalogenys analis)的种质资源情况以及群体的遗传多样性和遗传结构,对于其增养殖实践尤为重要。微卫星分子标记在研究物种种质情况及遗传信息方面有很大优势。采用基因组survey测序方法开发横带髭鲷微卫星位点,结果表明... 探究横带髭鲷(Hapalogenys analis)的种质资源情况以及群体的遗传多样性和遗传结构,对于其增养殖实践尤为重要。微卫星分子标记在研究物种种质情况及遗传信息方面有很大优势。采用基因组survey测序方法开发横带髭鲷微卫星位点,结果表明,横带髭鲷基因组大小为543Mb;微卫星位点丰富,共检测到280378个完美型微卫星位点,相对丰度为415.17个/Mb。二核苷酸重复是最丰富的微卫星类型(56.05%),其次为单核苷酸(29.20%)、三核苷酸(10.28%)、四核苷酸(2.99%)、五核苷酸(1.03%)、六核苷酸(0.45%)重复,短序列重复类型占95.53%。重复单元中A/T,TG/CA为优势重复单元,分别占总微卫星位点数的22.37%和21.98%;10次重复和6次重复的微卫星位点数量最多,占横带髭鲷基因组微卫星总数的14.60%和12.46%。利用筛选出的20对多态性微卫星位点扩增一个供试群体进行群体遗传学检测。结果表明,各位点等位基因数从5到13不等,均值为8.75个;平均观测杂合度(Ho)和期望杂合度(He)分别为0.808和0.863;多态信息含量(PIC)均值为0.826,且均大于0.5。经Bonferroni校正后有5个位点显著偏离哈迪–温伯格平衡(P<0.001);有4个位点存在无效等位基因。研究结果中的微卫星位点可用于今后横带髭鲷遗传育种和群体遗传学的研究。 展开更多
关键词 横带髭鲷 基因组survey 微卫星
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Survey Solution电子问卷调查系统应用与展望 被引量:1
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作者 崔艺 张颖 赵启然 《农业大数据学报》 2023年第4期81-85,共5页
在数据急剧增长的信息时代,网络技术的快速发展给传统问卷调查带来新挑战。电子问卷调查系统崭露头角,其被广泛应用到多个领域。本文以世界银行开发的Survey Solution电子问卷调查系统为例,全面介绍Survey Solution电子问卷调查系统特点... 在数据急剧增长的信息时代,网络技术的快速发展给传统问卷调查带来新挑战。电子问卷调查系统崭露头角,其被广泛应用到多个领域。本文以世界银行开发的Survey Solution电子问卷调查系统为例,全面介绍Survey Solution电子问卷调查系统特点,系统组件和功能,数据质量控制和核查方法,探讨Survey Solution系统的应用价值和使用建议。Survey Solution系统具有获取各种数据、严格调查数据质量、支持多种调查模式、安全且灵活的特点。Survey Solution系统主要组件包含总部系统(Headquarter)、问卷设计器(Designer)、调查软件(Interviewer)、主管(Supervisor),不同组件间协同工作,分别负责和实现不同的任务和功能,为数据收集和调查提供全面的支持。Survey Solution系统具有高质量数据收集、多样性的数据收集方式、实时数据监控和管理以及定制化数据处理和报告等应用价值。在使用Survey Solution系统时,要详细规划调查任务、培训调查员和主管、定期备份数据、使用数据分析工具以及及时解决问题,利用好Survey Solution提供一系列资源,最大程度地提高调查效率和数据质量。 展开更多
关键词 survey Solution 电子问卷调查系统 应用与展望
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基于基因组survey数据的疣吻沙蚕微卫星特征分析及多态标记开发
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作者 杨尉 司圆圆 +1 位作者 许瑞雯 陈兴汉 《南方水产科学》 CAS CSCD 北大核心 2023年第5期123-133,共11页
为了解疣吻沙蚕(Tylorrhynchus heterochaetus)基因组信息并高效地开发微卫星标记,指导其种质资源保护与新品种的遗传改良研究,采用低深度高通量测序开展全基因组survey,k-mer分析估计疣吻沙蚕基因组大小为759.53 Mb,杂合率1.41%,重复... 为了解疣吻沙蚕(Tylorrhynchus heterochaetus)基因组信息并高效地开发微卫星标记,指导其种质资源保护与新品种的遗传改良研究,采用低深度高通量测序开展全基因组survey,k-mer分析估计疣吻沙蚕基因组大小为759.53 Mb,杂合率1.41%,重复序列比例45.92%;初步组装获得2181621条scaffold,全长为840375821 bp。在基因组序列中检测到130216个微卫星位点,丰度为154.9个·Mb^(−1)。微卫星重复次数集中在4~18拷贝;单碱基重复比例最高(35.00%),二碱基(32.48%)、三碱基(14.42%)次之;二碱基、三碱基优势基序分别是AT/AT、AAT/ATT,表现出A/T碱基优势。从随机挑选的50对引物中筛选到15对多态标记,在30尾样本中共检测到87个等位基因,等位基因数(N_(a))为2.000~12.000(平均5.800),有效等位基因数(Ne)为1.164~6.713(平均3.328),期望杂合度(H_(e))为0.141~0.789(平均0.561),多态信息含量(PIC)为0.136~0.776(平均0.511);其中13个为高度或中度多态性位点,在遗传分析中有较高的实用价值。结果表明,疣吻沙蚕基因组为复杂基因组,其微卫星位点类型丰富且具备良好的多态性潜能,可为种质资源评价、群体遗传学及分子育种研究提供有效的标记资源。 展开更多
关键词 疣吻沙蚕 全基因组survey 简单重复序列 多态性位点
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Hyperspectral Image Super-Resolution Meets Deep Learning:A Survey and Perspective 被引量:2
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作者 Xinya Wang Qian Hu +1 位作者 Yingsong Cheng Jiayi Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第8期1668-1691,共24页
Hyperspectral image super-resolution,which refers to reconstructing the high-resolution hyperspectral image from the input low-resolution observation,aims to improve the spatial resolution of the hyperspectral image,w... Hyperspectral image super-resolution,which refers to reconstructing the high-resolution hyperspectral image from the input low-resolution observation,aims to improve the spatial resolution of the hyperspectral image,which is beneficial for subsequent applications.The development of deep learning has promoted significant progress in hyperspectral image super-resolution,and the powerful expression capabilities of deep neural networks make the predicted results more reliable.Recently,several latest deep learning technologies have made the hyperspectral image super-resolution method explode.However,a comprehensive review and analysis of the latest deep learning methods from the hyperspectral image super-resolution perspective is absent.To this end,in this survey,we first introduce the concept of hyperspectral image super-resolution and classify the methods from the perspectives with or without auxiliary information.Then,we review the learning-based methods in three categories,including single hyperspectral image super-resolution,panchromatic-based hyperspectral image super-resolution,and multispectral-based hyperspectral image super-resolution.Subsequently,we summarize the commonly used hyperspectral dataset,and the evaluations for some representative methods in three categories are performed qualitatively and quantitatively.Moreover,we briefly introduce several typical applications of hyperspectral image super-resolution,including ground object classification,urban change detection,and ecosystem monitoring.Finally,we provide the conclusion and challenges in existing learning-based methods,looking forward to potential future research directions. 展开更多
关键词 Deep learning hyperspectral image image fusion image super-resolution survey
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