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National Social Investment Programmes in Nigeria:A Descriptive Analysis of the Socio-Economic Contributions of N-Power Programme in Benue State
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作者 Robert Idoko Ogwola Dennis Anyebe Olofu Charles Amobi Aneke 《Management Studies》 2024年第1期9-20,共12页
This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue State.Prior to the introduction of N-Power programme,successive administrations in Nigeria hav... This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue State.Prior to the introduction of N-Power programme,successive administrations in Nigeria have made concerted efforts towards improving the standard of living of the citizenry through the execution of various welfare or social intervention programmes,but not much successes were recorded.Learning from the mistakes of the past regimes,and by way of deliberate state policy,the Buhari’s government initiated a multi-pronged social investment policy,one of which is the N-power programme that came onboard in 2016,which also doubles as the subject of this study.To achieve the goal of this study,a combination of desktop research and survey design was employed.Questionnaires were administered to 390 respondents through a combination of stratified and random sampling techniques.The results of the survey were matched with that of the secondary data obtained through online websites and other related sources.The result indicated that N-Power made positive contributions to the socio-economic life of the beneficiaries in Benue State:specifically,the scheme contributed in poverty eradication,employment generation,skills acquisitions and capacity building.However,some aspect of our findings revealed that the programme has a number of challenges such as:inadequate cash support,delay in monthly cash transfer to beneficiaries,distance participants had to move to their work stations,absence of posting in N-Teach scheme,and lack of adequate working tools amongst others.To salvage this problem the paper recommended the following solutions:expansion of the scheme to cover N-Teach and other aspects,increment in the monthly cash transfer to cushion the high rate of inflation,support for the participants/beneficiaries in transportation and logistics,enrolment of more youth into the various schemes,proper monitoring and evaluation of the implementation of the schemes amongst others. 展开更多
关键词 NATIONAL social investment programme N-Power CONTRIBUTIONS socio-economic development
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Are the altitudinal patterns of plant diversity derived from field surveys consistent with those from empirical integrated methods?
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作者 ZHAN Qing-hua FU Zhi-hao +2 位作者 ZHOU Ya-dong YAN Xue WANG Qing-feng 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1307-1315,共9页
Field surveys and empirical integrated methods are commonly used in the ecological research to understand the altitudinal pattern of plant diversity of mountains.However,few studies have compared the differences betwe... Field surveys and empirical integrated methods are commonly used in the ecological research to understand the altitudinal pattern of plant diversity of mountains.However,few studies have compared the differences between the two methods on the same scale.Here,we addressed and compared the altitudinal patterns of species richness(SR),phylogenetic diversity(PD),the standardized effect size of phylogenetic diversity(PDses)and mean phylogenetic distance(MPDses)of about 580 angiosperms growing on Mount Kenya from two independent datasets:one is based on our several times field surveys in this mountain and another one is based on empirical data integrated from literatures.We found that the altitudinal diversity patterns of field surveys dataset were consistent with the empirical integrated dataset.Both SR and PD showed hump-shaped patterns along the altitude,and both PDses and MPDses showed monotonically decreasing patterns along the altitude.The ratio of diversity between field surveys dataset and empirical integrated dataset were gradually increase along the altitude.Our research provides new insight for understanding the altitudinal diversity patterns of plants of a tropical mountain. 展开更多
关键词 Mount Kenya AFRICA surveys Interpolation method TAXONOMIC PHYLOGENETIC
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Socio-Economic and Technical Characteristics of Beef Cattle Breeding in Ndé Division, West Region of Cameroon
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作者 David Fokom Wauffo Geraud C. Tasse Taboue +10 位作者 Brenda M. Tsana Nantia Gina France Djoumessi Tobou Elvis Ndukong Ndzi Abdou S. Nsangou Mohamed M. F. Ndebé Brice H. T. Fokouong Frank D. K. Wouembe Suzy G. Tsoupou Kuete Kingsley M. Tanyi Kingsley A. Etchu Fernand Tendongkeng 《Open Journal of Animal Sciences》 2023年第3期379-397,共19页
Insight is here provided into the socio-economic and technical characteristics of cattle production in the Ndé Division (West Cameroon region). Using a semi-structured questionnaire, information on the activity w... Insight is here provided into the socio-economic and technical characteristics of cattle production in the Ndé Division (West Cameroon region). Using a semi-structured questionnaire, information on the activity was assessed following onsite visits and interviewing breeders. Through a random sampling scheme, 110 breeders in the four subdivisions of the Ndé Division were shadowed. The majority (98.18%) of breeders were men aged 20 to 40 and married (91.82%). They belong to the Mbororo ethnic group, having cumulated more than 10 years in the activity. Most respondents (50.91%) did not attend school and earn their living mainly from livestock (78.18%). Cattle were raised for sale and to feed the breeder’s family (77.27%). The main mode of acquisition of animals was through inheritance (81.82%). The cattle breeds were mostly made up of white Fulani (70%), living in private farms using a combination of stake and barbed wires (67.27%) as fences. The combination of natural fodder and cooking salt was used by most breeders (59.09%) as a daily ration. Reproduction was by natural mating (97.07%). Parasites (internal and external) and foot-and-mouth disease were the main diseases reported by the majority of farmers. Self-treatment (50%) was the main prophylactic measure taken by farmers in case of disease symptoms. Cattle herders faced several challenges, such as insufficient pasture (67.27%), agro-pastoral conflicts (76.36%) and diseases (90.91%). Cattle breeding was rather a widespread activity with no particular restriction. 展开更多
关键词 Cattle Breeding socio-economic BREEDING Technical Characteristics CONSTRAINTS Cameroon
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Socio-Economic Characteristics of Three Artisanal Fisheries Communities in the Northern Sudanese Red Sea Coast
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作者 Abdelmoneim Karamalla Gaiballa Omar Abdulkadir Mahadalle 《Open Journal of Ecology》 2023年第11期820-835,共16页
Socio-economic characteristics related to fishing gears and boats from three selected small-scale fishers’ communities (Oseif, Dungonab and Mohammed Qol) in the northern part of the Sudanese Red Sea coast were studie... Socio-economic characteristics related to fishing gears and boats from three selected small-scale fishers’ communities (Oseif, Dungonab and Mohammed Qol) in the northern part of the Sudanese Red Sea coast were studied. The study was designed to provide base line data and information on the current socio-economic situation, factors that determine the use of fishing gear, types of boats and fishing equipment, challenges facing fishers and the extent to which fishing gear and boats are related with the socio-economic characteristics of the fishers community in the study sites. Fieldwork was carried out during 2016. The study methods included a series of interviews based on questionnaires, field observations and focus group discussions. The results of the study showed that the most common fishing gears are handlines, cast nets and gillnets. The two types of boats used at the study sites are motorized fiberglass and houri (motorized and paddled) with a V-shaped hull. Boat ownership varies among fishers. Each fisher can have several types of gears in different numbers. Target fish species, season, efficiency of gear and fishing location were the main factors determining the use of fishing gear at study sites, respectively. All fishers are men and most have families of at least four people. The majority of fishers are between 21 and 50 years old and work mainly in fishing. They inherited fishing knowledge within the family, and most of them have been working in artisanal fishing for more than 10 years. Fishers have relatively good net incomes compared to other government employers in the study sites. Most fishers work full time in fishing. A small number of fishers work part-time with the possibility of undertaking other income-generating activities such as animal husbandry and seasonal agriculture. The main challenges identified by fishers at the study sites were fish prices, sea surface roughness and high cost of fishing materials, respectively. Most fishers perceived a recent decline in both catch size and abundance. 展开更多
关键词 Red Sea of Sudan GEARS Boats Small Scale Fishers socio-economic
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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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Low Socio-Economic Level: A Major Obstacle to Therapeutic Observation (Survey of 125 Diabetic Patients)
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作者 Ousseynou Ka Djiby Sow +6 位作者 Elhadji Mouhamadou Seck Ndeye Fatou Ngom Guéye Martial Coly Bop Mountaga Elimane Dia Abdoul Aziz Ndiaye Papa Gallo Sow Maimouna Mbaye Ndour 《Open Journal of Preventive Medicine》 2022年第1期1-9,共9页
<strong>Introduction:</strong> Diabetic patients adhering to their treatment are less likely to face complication from their disease. For this reason, we studied the compliance of diabetics with their trea... <strong>Introduction:</strong> Diabetic patients adhering to their treatment are less likely to face complication from their disease. For this reason, we studied the compliance of diabetics with their treatment. <strong>Materials and Method:</strong> This was a comprehensive cross-sectional study of adherence in diabetic patients. All patients meeting the inclusion criteria were enrolled in the study. This study took place at a private pharmacy called “pharmacy Elhadj Seydou Nourou Tall” located in the city of Pikine during the period from April 1 to September 30, 2019. <strong>Results:</strong> In total, the study population was composed of 125 diabetics;frequency of 8.47%. The average age was 62.5 years and there were more women (58.4%). Of the patients, 87% had a low socioeconomic level and 72% a low educational level. Only 65.6% of the patients knew their diabetes type. Even though 97.6% of the patients were confident in the treatment but due to financial reasons 20.8% did not adhere to the prescribed treatment and 16.8% to their diets. Moreover, 15.2% of the patients had changed the dosage of the prescribed medication, 44.4% had forgotten to take their medication regularly. 78.4% of them thought they were taking too much medication. No factors were found to be statistically associated with poor adherence, but the proportion of poor adherence patients was higher in patients over 60 years of age, with low socio-economic status and low education. <strong>Conclusion:</strong> Low socio-economic status is the main barrier to good adherence. Recommendations have been formulated to improve this adherence. 展开更多
关键词 ADHERENCE DIABETES socio-economic Level BARRIER Senegal
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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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Insync Surveys图书馆用户满意度调查分析 被引量:8
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作者 张为杰 杨广锋 周婕 《图书情报知识》 CSSCI 北大核心 2009年第6期34-38,86,共6页
Insync Surveys,原名Ambit Insights/Rodski Survey Research,是澳大利亚一家调查服务公司。其用户满意度调查自1998年在墨尔本大学图书馆实施以来,影响不断扩大,并与CAUL建立了稳定的合作关系。Insync Surveys以关注度-满意度为方法基... Insync Surveys,原名Ambit Insights/Rodski Survey Research,是澳大利亚一家调查服务公司。其用户满意度调查自1998年在墨尔本大学图书馆实施以来,影响不断扩大,并与CAUL建立了稳定的合作关系。Insync Surveys以关注度-满意度为方法基础,指标体系灵活调整,并提供基本调查和全面调查两种服务模式,取得了良好的实践效果。 展开更多
关键词 Insync surveys Rodski 满意度调查 服务质量评估
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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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Research progress of socio-economic water cycle in China 被引量:6
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作者 JIA Shao-feng, WANG Guo, ZHANG Shi-feng, YU Gui-rui, WANG Jin-xia, XIA Jun (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101,China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第1期114-120,共7页
China has made great progress in the study of socio-economic water cycle. She has completed national water resources appraisement and medium to long-term water supply planning. She has been engaging in study on water-... China has made great progress in the study of socio-economic water cycle. She has completed national water resources appraisement and medium to long-term water supply planning. She has been engaging in study on water-deficient regions in North China and Northwest China for about half a century. For solving water shortage problem in northern China, she has put forward the famous South-to-North Water Transferring Projects, which has been set as one of the four biggest national projects in the Tenth Five-Year-Plan period although there are still debates. For promoting water use efficiency, China has been reforming her water management system, including water right system and water price system. There has already been a case of water right purchase. China has also done a lot of research on the interaction between human activity, water and ecosystem. For meeting the need of sustainability and coordinating water resources development and environmental protection, the study of ecological water requirement became very hot in recent years. There are three focuses of socio-economic water cycle study now in China: water transfer projects from the south to the north, water resources management and ecological water requirement. 展开更多
关键词 water cycle socio-economic water cycle sustainable water resources management water security
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Influence of Climate and Socio-Economic Factors on the Spatio-Temporal Variability of Soil Organic Matter: A Case Study of Central Heilongjiang Province, China 被引量:4
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作者 SHI Shu-qin CAO Qi-wen +6 位作者 YAO Yan-min TANG Hua-jun YANG Peng WU Wen-bin XU Heng-zhou LIU Jia LI Zheng-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第7期1486-1500,共15页
For the scientific management of farmland, it is significant to understand the spatio-temporal variability of soil organic matter and to study the influences of related factors. Using geostatistical theory, GIS spatia... For the scientific management of farmland, it is significant to understand the spatio-temporal variability of soil organic matter and to study the influences of related factors. Using geostatistical theory, GIS spatial analysis, trend analysis and a Geographically Weighted Regression (GWR) model, this study analyzed the response of soil organic matter to climate and socio-economic factors in central Heilongjiang Province during the past 25 years. Second soil survey data of China for 1979-1985, 2005 field sampling data, climate observations and socio-economic data for 1980-2005 were analyzed. First, soil organic matter in 2005 was spatially interpolated using the Co-Kriging method along with auxiliary data sets of soil type and pH. The spatio-temporal variability was then studied by comparison with the 1980s second soil census data. Next, the temporal trends in climate and socio-economic factors over the past 25 years were investigated. Finally, we examined the variation of the response of soil organic matter to climate and socio-economic factors using the GWR model spatially and temporally. The model showed that 53.82% area of the organic matter content remained constant and 29.39% has decreased during the past 25 years. The impact of precipitation on organic matter content is mainly negative, with increasing absolute values of the regression coefficient. The absolute value of regression coefficient of annual average temperature has decreased, and more areas are now under its negative effects. In addition, the areas of positive regression coefficient of annual sunshine hours have northward shifted, with the increasing absolute value of positive coefficient and decreasing absolute value of negative coefficient. The areas of positive regression coefficient of mechanized farming as a socio-economic factor have westward shifted, with the increasing absolute value of negative coefficient and decreasing absolute value of positive coefficient. The area of regions with the positive regression coefficient of irrigation has expanded. The regions with positive regression coefficient of fertilizer use have shrinked. The positive regression coefficient of mulch film consumption has significantly increased. The regression coefficient of pesticide consumption was mainly positive in the west of the study area, while it was negative to the east. Generally, GWR model is capable to investigate the influence of both climatic and socio-economic factors, avoided the insufficiency of other research based on the single perspective of climatic or socio-economic factors. Therefore, we can conclude that GWR model could provide methodological support for global change research and serve as basic reference for cultivated land quality improvement and agricultural decision making. 展开更多
关键词 soil organic matter CLIMATE socio-economic factors GWR Heilongjiang Province
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Analysis of the Results of Two Nationwide Surveys on Clonorchis sinensis Infection in China 被引量:22
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作者 CHEN Ying Dan ZHOU Chang Hai XU Long Qi 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第2期163-166,共4页
Objective To examine Clonorchis sinensis infection in China and evaluate the effectiveness of efforts to prevent and control it,two nationwide surveys were undertaken in 31 provinces,autonomous regions,and municipalit... Objective To examine Clonorchis sinensis infection in China and evaluate the effectiveness of efforts to prevent and control it,two nationwide surveys were undertaken in 31 provinces,autonomous regions,and municipalities(PAMs) during 1988-92(the 1990 survey) and during 2001-04(the 2003 survey).Methods During the period 2001-04,two sampling methods were applied.The first method repeated the stratified cluster random sampling used in the 1990 survey;the second method applied two-characteristic stratified cluster random sampling in 27 PAMs—the 2003 endemic area(EA) survey.The Kato-Katz thick smear method was used for the nationwide survey.Results The infection rates of Clonorchis sinensis in the 1990 and 2003 surveys were 0.311% and 0.579%,respectively.The infection rate was 2.40% in the 2003 EA survey,and it was estimated that 12.49 million people in China were infected with Clonorchis sinensis.Conclusion The 2003 survey showed that the standardized infection rate of Clonorchis sinensis increased by 74.85% compared with the 1990 survey.The infection rate in males was higher than in females;the infection rate among people eating raw fish or eating out frequently was higher than among those who did not. 展开更多
关键词 Clonorchis sinensis Two nationwide surveys The status of infection in China
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ECOLOGICAL AND SOCIO-ECONOMIC REHABILITATION IN THE KARST OF SOUTHWEST CHINA 被引量:5
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作者 Cai Yunlong Department of Geography, Peking University, Beijing 100871 People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第2期24-32,共9页
The Karst of Southwest China is a typical representative of poverty stricken region with impoverishment-degradation spiral. To essentially break away from this vicious circle, the local ecology, economy and society s... The Karst of Southwest China is a typical representative of poverty stricken region with impoverishment-degradation spiral. To essentially break away from this vicious circle, the local ecology, economy and society should be rehabilitated, and hence to strengthen the self-development capacity building of the localities. Two considerations are stressed in this article: (1) Poverty alleviation is a system project with great complexities. Any single approach is difficult to success and integrated measures should be taken. (2) Some typical and feasible areas should be selected to demonstrate the project of poverty alleviation and ecological, socio-economic reconstruction. Then, they can be used as a model to promote the sustainable development of the whole region. Based upon these ideals, a project entitled “Reversal of Impoverishment-Degradation Spiral in the Karst of Southwest China' was proposed and has been listed in 《Priority Programme for China's Agenda 21》. 展开更多
关键词 poverty alleviation environmental degradation capacity building ecological and socio-economic rehabilitation karst areas Southwest China.
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