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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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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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Field survey and analysis on near-fault severely damaged high-speed railway bridge in 2022 M6.9 Menyuan earthquake
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作者 Lin Xuchuan Liu Fuxiang Shan Wenchen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期1043-1055,共13页
The 2022 M6.9 Menyuan earthquake caused severe damage to a high-speed railway bridge,which was designed for high-speed trains running at speeds of above 250 km/h and is located right next to the fault.Bridges of this ... The 2022 M6.9 Menyuan earthquake caused severe damage to a high-speed railway bridge,which was designed for high-speed trains running at speeds of above 250 km/h and is located right next to the fault.Bridges of this type have been widely used for rapidly constructing the high-speed railway network,but few bridges have been tested by near-fault devastating earthquakes.The potential severe impact of the earthquake on the high-speed railway is not only the safety of the infrastructure,trains and passengers,but also economic loss due to interrupted railway use.Therefore,a field survey was carried out immediately after the earthquake to collect time-sensitive data.The damage to the bridge was carefully investigated,and quantitative analyses were conducted to better understand the mechanism of the bridge failure.It was found that seismic action perpendicular to the bridge’s longitudinal direction caused severe damage to the girders and rails,while none of the piers showed obvious deformation or cracking.The maximum values of transverse displacement,out-of-plane rotation and twisting angle of girders reached 212.6 cm,3.1 degrees and 19.9 degrees,respectively,causing severe damage to the bearing supports and anti-seismic retaining blocks.These observations provide a basis for improving the seismic design of high-speed railway bridges located in near-fault areas. 展开更多
关键词 Menyuan earthquake field survey high-speed railway bridge near fault seismic damage
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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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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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中国龙船花基因组Survey分析
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作者 涂绍强 柯玲俊 +2 位作者 蔡月琴 陆銮眉 余惠文 《亚热带植物科学》 CAS 2024年第3期214-219,共6页
中国龙船花Ixora chinensis是一种兼备药用与观赏价值的传统中药材,解析中国龙船花的基因组特征信息,可为其全基因组测序和药效成分生物合成的分子机制研究奠定理论基础。本研究利用Survey基因组测序技术,使用K-mer分析方法对中国龙船... 中国龙船花Ixora chinensis是一种兼备药用与观赏价值的传统中药材,解析中国龙船花的基因组特征信息,可为其全基因组测序和药效成分生物合成的分子机制研究奠定理论基础。本研究利用Survey基因组测序技术,使用K-mer分析方法对中国龙船花基因组特征信息展开评估,获得基因组重复度、杂合度以及GC含量等信息。Survey高通量测序获得Raw Data 47.63 Gb,过滤后Clean data 45.62 Gb。K-mer分析表明,基因组大小588.35 Mb,杂合度1.5598%,重复度64.49%,GC含量35.71%,中国龙船花基因组呈现高杂合度、高重复度、基因组庞大的特征。 展开更多
关键词 中国龙船花 高通量测序 基因组survey K-mer分析 杂合度 重复序列
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Research surveys and their evolution:Past,current and future uses in healthcare
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作者 Michael Colwill Richard Pollok Andrew Poullis 《World Journal of Methodology》 2024年第4期91-95,共5页
Research surveys are believed to have originated in antiquity with evidence of them being performed in ancient Egypt and Greece.In the past century,their use has grown significantly and they are now one of the most fr... Research surveys are believed to have originated in antiquity with evidence of them being performed in ancient Egypt and Greece.In the past century,their use has grown significantly and they are now one of the most frequently employed research methods including in the field of healthcare.Modern validation techniques and processes have allowed researchers to broaden the scope of qualitative data they can gather through these surveys such as an individual’s views on service quality to nationwide surveys that are undertaken regularly to follow healthcare trends.This article focuses on the evolution and current utility of research surveys,different methodologies employed in their creation,the advantages and disadvantages of different forms and their future use in healthcare research.We also review the role artificial intelligence and the importance of increased patient participation in the development of these surveys in order to obtain more accurate and clinically relevant data. 展开更多
关键词 Research surveys METHODOLOGY Sampling Artificial intelligence
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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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鳓鱼全基因组survey分析及微卫星位点分布
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作者 高鲁修 陈诗逸 +5 位作者 冯桃波 刘炳舰 柳意樊 沈豪迪 黄文化 梁旭东 《水产科技情报》 2024年第5期283-289,共7页
为研究鳓鱼(Ilisha elongata)的遗传演化概况,对鳓鱼基因组进行了高通量测序并开展了survey分析和基因组范围内的遗传标记开发。K-mer分析结果显示,鳓鱼基因组大小约为692.8 Mb,杂合率为0.18%,重复序列比例为39.6%。基因组初步组装Scaff... 为研究鳓鱼(Ilisha elongata)的遗传演化概况,对鳓鱼基因组进行了高通量测序并开展了survey分析和基因组范围内的遗传标记开发。K-mer分析结果显示,鳓鱼基因组大小约为692.8 Mb,杂合率为0.18%,重复序列比例为39.6%。基因组初步组装Scaffold N50为27694 bp,Contig N50为6306 bp。利用MISA软件对鳓鱼基因组的微卫星标记(simple sequence repeat,SSR)进行检索和分析,总共检测到786123个SSR位点,相对丰度为1204个/Mb。在所有类型中,重复最多的是二碱基,占SSR总量的75.94%,其SSR重复频率主要集中在6~28次;其次为单碱基和四碱基,分别占SSR总量的15.31%和4.25%。对二碱基类型而言,AC型具有最多的重复数量,为131732个,单碱基重复数量最多的则是A型,有48775个。研究结果表明,鳓鱼基因组经组装后可得到高质量的全基因组序列,经过筛选的SSR位点可为后续的遗传分子标记开发提供有力支持,研究结果可为鳓鱼种质资源管理和保护、生物进化和群体遗传等研究工作提供基础资料。 展开更多
关键词 鳓鱼 全基因组survey 微卫星标记 高通量测序 生物遗传
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Survey and Analysis of Postoperative Quality of Life in Gynaecological Oncology Patients
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作者 Yujing Zhou Fengjuan Yuan +6 位作者 Moyu Shang Xiaoyu Chang Haiyue Huang Shirui Wang Xuanxiang Bian Qixuan Gao Yanan Dai 《Journal of Advances in Medicine Science》 2024年第1期7-14,共8页
Goal:To investigate the current status of quality of life of postoperative patients with gynaecological tumours,and to analyse the relevant factors affecting the quality of life of postoperative patients with gynaecol... Goal:To investigate the current status of quality of life of postoperative patients with gynaecological tumours,and to analyse the relevant factors affecting the quality of life of postoperative patients with gynaecological tumours.Method:One hundred and fifty-three postoperative gynecological oncology patients who attended the gynaecology and oncology departments of three tertiary hospitals in Henan Province from June 2023 to March 2024 were investigated by convenience sampling method.The patients’postoperative survival quality was investigated through the General Information Survey Scale and Quality of Life Score Scale.Results:The quality of life measurement scale score of postoperative gynaecological oncology patients in this study was(121.27±10.87),in which there was a difference in the quality of life of postoperative gynaecological oncology patients of different age,education level,marital status,and per capita monthly income of the family,p<0.05.Conclude:The quality of life level of postoperative gynaecological oncology patients is generally good,and age,literacy,marital status,and per capita monthly family income are important factors in the postoperative quality of life of gynaecological oncology patients.Healthcare professionals should focus on patients with older age,lower education level,unstable marital status,and poor economic status,and provide personalised targeted interventions to improve their quality of life. 展开更多
关键词 Gynaecological oncology Quality of life Current status survey
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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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Characteristics of B,Zn and Se in stream sediments of Tanzania and their agricultural applications:Based on 1∶1000000 geochemical survey
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作者 Kang-kang Xu Hong-wei Sun +7 位作者 Wei Xie Fu-qing He Xiao-yang Liu Kai Sun Sheng-fei He Xing-yuan Wu Peng-hui Gong Godfrey Machumu 《China Geology》 CAS CSCD 2023年第1期1-14,共14页
Tanzania is located in eastern Africa with a predominantly agricultural ecomomy,the potential for developing and utilizing cultivated land are promising,but scientific guidance is required.B,Zn and Se are essential mi... Tanzania is located in eastern Africa with a predominantly agricultural ecomomy,the potential for developing and utilizing cultivated land are promising,but scientific guidance is required.B,Zn and Se are essential micronutrients for plants and human body with crucial biological functions,in particular,Se is significant for human health and considered as“the king of anti-cancer”.As these elements required by human or plants are mainly absorbed from soil directly or indirectly,therefore,it is important to understand the contents and distributions of them in the soil of cultivated land for guiding agricultural production.In this work,low-density geochemical survey at the scale of 1∶1000000 was carried out in Tanzania,and the results show that the concentrations of B,Zn and Se in stream sediments are low and their distributions are heterogeneous.According to the distributions of geological units,the existing cultivated land resources can be divided into five regions in Tanzania.Compared with the national background values,the concentrations of B,Zn and Se are insufficient overall but enriched locally in these regions.In general,element concentrations in stream sediments and soil have a positive correlation because of their similar sources,which is essential in agriculture application.Based on the information provided by low-density geochemical data and maps,the Se-sufficient and Se-rich regions were delineated in Tanzania,where can be used to develop Se-rich industries.Finally,this paper believes that geochemical survey is a powerful tool for cultivated land evaluation,agriculture management and land development. 展开更多
关键词 Stream sediment Low-density geochemical survey Geochemical map Soil of cultivated land Agricultural applications Agricultural geological survey engineering Tanzania Selenium-rich agricultural products
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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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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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