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Influence of a large dam on the longitudinal patterns of fish assem- blages in Qingyi Stream 被引量:5
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作者 Xiao-Yun SUI Zhi LU +2 位作者 Yun-Zhi YAN Yi-Feng CHEN Yin-Tao JIA 《Zoological Research》 CAS CSCD 北大核心 2014年第5期362-372,共11页
Using seasonally collected data(2009-2010) from 15 sampling sites that represent first- to fifth-order streams within the Qingyi watershed,we examined the spatio-temporal patterns of fish assemblages along two longitu... Using seasonally collected data(2009-2010) from 15 sampling sites that represent first- to fifth-order streams within the Qingyi watershed,we examined the spatio-temporal patterns of fish assemblages along two longitudinal gradients to explore the effects of a large dam on fish assemblages at the watershed scale.No significant variation was observed in either species richness or assemblage structure across seasons.Species richness significantly varied according to stream order and gradient.Dam construction appeared to decrease species richness upstream substantially,while a significant decrease between gradients only occurred within fourth-order streams.Along the gradient without the large dam,fish assemblage structures presented distinct separation between two neighboring stream orders,with the exception of fourth-order versus fifth-order streams.However,the gradient disrupted by a large dam displayed the opposite pattern in the spatial variation of fish assemblages related with stream orders.Significant between-gradient differences in fish assemblage structures were only observed within fourth-order streams.Species distributions were determined by local habitat environmental factors,including elevation,substrate,water depth,current discharge,wetted width,and conductivity.Our results suggested that dam construction might alter the longitudinal pattern in fish species richness and assemblage structure in Qingyi Stream,despite the localized nature of the ecological effect of dams. 展开更多
关键词 fish assemblage species richness spatiotemporal pattern Longitudinal gradient Dam building
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Spatio-Temporal Variations in Co-Occurrence Patterns of Fish Communities in Haizhou Bay, China: Null Model Analysis
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作者 WANG Jiao ZHANG Chongliang +3 位作者 XUE Ying CHEN Yong REN Yiping XU Binduo 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第6期1497-1506,共10页
Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patte... Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patterns of fish species were examined using the C-score under fixed-fixed null model for fish communities in spring and autumn over different years in the Haizhou Bay,China.The results showed that fish assemblages in the whole bay had non-random patterns in spring and autumn over different years.However,the fish co-occurrence patterns were different for the northern and southern fish assemblages in spring and autumn.The northern fish assemblage showed structured pattern,whereas the southern assemblage were randomly assembled in spring.The co-occurrence patterns of fish communities were relatively stable over different years,and the number of significant species pairs in northern assemblage was more than that in the southern assemblage.Environmental heterogeneity played an important role in determining the distributions of fish species that formed significant species pairs,which might affect the co-occurrence patterns of northern and southern assemblages further in the Haizhou Bay. 展开更多
关键词 fish COMMUNITY Haizhou BAY NULL model analysis sPECIEs CO-OCCURRENCE pattern
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基于FISH和GISH技术的芝麻栽培种和野生种染色体组特征比较分析
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作者 马琴 赵瑞红 +5 位作者 琚铭 陈成彬 段迎辉 杨伟飞 苗红梅 张海洋 《河南农业科学》 北大核心 2024年第10期48-53,共6页
为揭示胡麻属物种进化特征,探究胡麻属基因组结构演变及物种进化,促进野生资源的开发利用,以芝麻栽培种豫芝11号和2n=26类型野生种S.alatum 3651为试验材料,采用荧光原位杂交(FISH)和基因组荧光原位杂交(GISH)技术对芝麻栽培种和野生种... 为揭示胡麻属物种进化特征,探究胡麻属基因组结构演变及物种进化,促进野生资源的开发利用,以芝麻栽培种豫芝11号和2n=26类型野生种S.alatum 3651为试验材料,采用荧光原位杂交(FISH)和基因组荧光原位杂交(GISH)技术对芝麻栽培种和野生种染色体组特征进行分析。结果表明,芝麻栽培种和野生种均为2n=2x=26类型;rDNA-FISH杂交结果显示,栽培种的13对染色体中,3对染色体(第7、8、9对染色体)的短臂端部携带45S rDNA特异信号,显示为随体特异染色体;2对染色体(第5、11对染色体)的短臂携带5S rDNA特异信号,5S rDNA与45S rDNA信号位于不同染色体上。野生种的13对染色体中,有2对染色体(第4、7对染色体)携带45S rDNA杂交信号,1对染色体(第4对染色体)携带5S rDNA特异信号,5S rDNA与45S rDNA信号位于同一染色体不同位置,表明栽培种与野生种的染色体组特征差异较大。GISH杂交结果显示,分别以栽培种和野生种的基因组DNA作探针与自身染色体杂交,每条染色体上携带不同强弱的杂交信号,而与对方染色体杂交,均表现出极少的杂交信号。芝麻栽培种和野生种具有相同的染色体数目,但染色体rDNA数量、分布及其GISH信号均存在明显差异,说明栽培种和野生种亲缘关系较远。 展开更多
关键词 芝麻 栽培种 野生种s.alatum 染色体组 rDNA 荧光原位杂交(fish) 基因组荧光原位杂交(GIsH)
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The forecasting efficiency under different selected regions by Pattern Informatics Method and seismic potential estimation in the North-South Seismic Zone
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作者 Weixi Tian Yongxian Zhang 《Earthquake Science》 2024年第4期368-382,共15页
In 2022,four earthquakes with M_(S)≥6.0 including the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes occurred in the North-South Seismic Zone(NSSZ),which demonstrated high and strong seismicity.Pattern Informatics(... In 2022,four earthquakes with M_(S)≥6.0 including the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes occurred in the North-South Seismic Zone(NSSZ),which demonstrated high and strong seismicity.Pattern Informatics(PI)method,as an effective long and medium term earthquake forecasting method,has been applied to the strong earthquake forecasting in Chinese mainland and results have shown the positive performance.The earthquake catalog with magnitude above M_(S)3.0 since 1970 provided by China Earthquake Networks Center was employed in this study and the Receiver Operating Characteristic(ROC)method was applied to test the forecasting efficiency of the PI method in each selected region related to the North-South Seismic Zone systematically.Based on this,we selected the area with the best ROC testing result and analyzed the evolution process of the PI hotspot map reflecting the small seismic activity pattern prior to the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes.A“forward”forecast for the area was carried out to assess seismic risk.The study shows the following.1)PI forecasting has higher forecasting efficiency in the selected study region where the difference of seismicity in any place of the region is smaller.2)In areas with smaller differences of seismicity,the activity pattern of small earthquakes prior to the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes can be obtained by analyzing the spatio-temporal evolution process of the PI hotspot map.3)The hotspot evolution in and around the southern Tazang fault in the study area is similar to that prior to the strong earthquakes,which suggests the possible seismic hazard in the future.This study could provide some ideas to the seismic hazard assessment in other regions with high seismicity,such as Japan,Californi,Turkey,and Indonesia. 展开更多
关键词 Luding M_(s)6.8 and Menyuan M_(s)6.9 earthquake pattern Informatics Method North-south seismic Zone earthquake forecasting seismic activity pattern.
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A Novel YOLOv5s-Based Lightweight Model for Detecting Fish’s Unhealthy States in Aquaculture
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作者 Bing Shi Jianhua Zhao +2 位作者 Bin Ma Juan Huan Yueping Sun 《Computers, Materials & Continua》 SCIE EI 2024年第11期2437-2456,共20页
Real-time detection of unhealthy fish remains a significant challenge in intensive recirculating aquaculture.Early recognition of unhealthy fish and the implementation of appropriate treatment measures are crucial for... Real-time detection of unhealthy fish remains a significant challenge in intensive recirculating aquaculture.Early recognition of unhealthy fish and the implementation of appropriate treatment measures are crucial for preventing the spread of diseases and minimizing economic losses.To address this issue,an improved algorithm based on the You Only Look Once v5s(YOLOv5s)lightweight model has been proposed.This enhanced model incorporates a faster lightweight structure and a new Convolutional Block Attention Module(CBAM)to achieve high recognition accuracy.Furthermore,the model introduces theα-SIoU loss function,which combines theα-Intersection over Union(α-IoU)and Shape Intersection over Union(SIoU)loss functions,thereby improving the accuracy of bounding box regression and object recognition.The average precision of the improved model reaches 94.2%for detecting unhealthy fish,representing increases of 11.3%,9.9%,9.7%,2.5%,and 2.1%compared to YOLOv3-tiny,YOLOv4,YOLOv5s,GhostNet-YOLOv5,and YOLOv7,respectively.Additionally,the improved model positively impacts hardware efficiency,reducing requirements for memory size by 59.0%,67.0%,63.0%,44.7%,and 55.6%in comparison to the five models mentioned above.The experimental results underscore the effectiveness of these approaches in addressing the challenges associated with fish health detection,and highlighting their significant practical implications and broad application prospects. 展开更多
关键词 Intensive recirculating aquaculture unhealthy fish detection improved YOLOv5s lightweight structure
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Forest landscape patterns dynamics of Yihe-Luohe river basin 被引量:4
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作者 DINGShengyan SHANGFude +2 位作者 QIANLexiang CAOXinxiang LIShuang 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期153-162,共10页
Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of t... Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of the typical region in the middle of the Yihe-Luohe river basin. These indices include patch number, mean patch area, fragment index, patch extension index, etc. The results showed that: (1) There was a rapid increase in the number of patch and total area from 1983 to 1999 in the study area. The fragment degree became very high. (2) The area of all the forest patch types had witnessed great changes. The fractal degree of each forest patch type became big from 1983 to 1999. The mean extension index of Robinia pseudoacacia forest, non-forest, shrub forest, sparse forest, and Quercus species forest increased rapidly, but that of economic forest became zero. The fractal dimension each showed that forest coverage has been promoted. (3) The changes of landscape patterns were different in different geomorphic regions. From 1983 to 1999 the vegetation cover area, the gross number and the density of patch, diversity and evenness of landscape were all reduced greatly in gullies and ravines, but the maximum area and the mean area of patch types were increased. In hilly region, both the forest cover area and the number of patch increased from 1983 to 1999, but the mean area of patch was reduced greatly. In mountain region, even though the area under forest canopy reduced from 1983 to 1999, the patch number was increased greatly, the mean area of all patch types was reduced, the extension index, diversity index and evenness index of landscape were all increased. Furthermore, because of different types of land use, human activity and terrain, the vegetation changes on northern and southern mountain slopes were different. According to these analyses, the main driving forces, such as the policies of management, market economy, influence of human activities etc. are brought out. 展开更多
关键词 FOREsT landscape pattern DYNAMICs geomorphic zone Yihe-Luohe river basin Luoning County CLC number:s718.5 Q948.2 P901
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Distribution Patterns of Medicinal Plants along an Elevational Gradient in Central Himalaya,Nepal 被引量:1
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作者 Maan B.ROKAYA Zuzana MÜNZBERGOVÁ +1 位作者 Mani R.SHRESTHA Binu TIMSINA 《Journal of Mountain Science》 SCIE CSCD 2012年第2期201-213,共13页
This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions,and between medicinal plants and all vascular plants.We used the pu... This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions,and between medicinal plants and all vascular plants.We used the published sources for elevation records of 2,331 medicinal plant species to interpolate presence between minimum and maximum elevations and estimated medicinal plant richness for each 100-m elevational band. Monte Carlo simulations were used to test whether differences in elevational distribution between different groups of medicinal plants were significant. Total number of medicinal plants as well as different groups showed unimodal relationship with elevation. The elevational distributions of medicinal plants significantly differ between regions and between medicinal plant groups.When comparing the richness of all medicinal plants to all vascular plants,Monte Carlo simulations indicated that the numbers of medicinal plants are higher than expected at low elevations.The highest richness of medicinal plants at low elevation could be possibly due to favorable environmental factors such as high temperature, rainfall,sunlight or due to higher density of human population and thus higher pressure on use of any plants in lower elevations. 展开更多
关键词 species richness Rapoport's elevational rule Mid-domain effect Randomization test Unimodal pattern HIMALAYA Nepal
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Change of Flood Patterns in China under the Influences of Climate Change and Human Activities 被引量:2
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作者 Yin Yixing Xu Youpeng Chen Ying 《Chinese Journal of Population,Resources and Environment》 2009年第3期67-71,共5页
Based on the flood affected area (FA) data of the provinces in China from 1950 to 2005, the article discusses the change of the flood patterns in China, and investigates its relationship with climate change and huma... Based on the flood affected area (FA) data of the provinces in China from 1950 to 2005, the article discusses the change of the flood patterns in China, and investigates its relationship with climate change and human activities. The flood center shifted from North China and the Yangtze-Huaihe basin in the 1950s towards the south, north and west of China, and located in the south of the Yangtze River and South China after the 1990s. The FA in the western provinces was continuously on the rise since the 1950s. There are two characteristics for the future flood pattem in China. The pattern of "flood in the south and drought in the north" depends on the north-south shift of the maximum rainfall region in eastern China. The flood intensification to the west of Hu Huanyong's line mainly results from the increase of rainfall, extreme precipitation and the melting of glaciers under the background of human activity magnification. 展开更多
关键词 flood pattern flood in the south and drought in the north Hu Huanyong's line climate change human activity
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Consumer Preference and Consumption Pattern of Marine Fish Species in Ibadan Metropolis, Oyo State, Nigeria
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作者 Tosan B. Fregene Adeniyi S. Olanusi 《Journal of Agricultural Science and Technology(B)》 2012年第7期835-840,共6页
Despite the nutritive value of finfish, the domestic production is inadequate to meet the national demand. Due to the high demand of 2.66 million metric tons per annum for fish, Nigeria imported 740,000 tons in 2007 t... Despite the nutritive value of finfish, the domestic production is inadequate to meet the national demand. Due to the high demand of 2.66 million metric tons per annum for fish, Nigeria imported 740,000 tons in 2007 to supplement the domestic production of 615,507 tons. A study was conducted in Ibadan Metropolis of Oyo State (a land locked state) to determine the consumer preference and pattern of marine fish species consumed. Stratified sampling method was used to select respondents from three income earning levels of the five local government areas in Ibadan Metropolis. Questionnaires were administered to 51 marine fish retailers and 151 households. Data collected was analyzed using descriptive statistics and Tobit regression model. Marine fish sellers ranked horse mackerel (Scomberjaponicus) first and croaker (Pseudotholithus species) the least because it is more priced. Only 10.6% and 13.2% of the households preferred express (Brevortia species) and croaker respectively, but Hake (Gadus gadus) was the least preferred (41.7%). The household consumed varying proportions of fish species every week. The regression result (R2 = 0.65) showed that married household heads with large household size having lower years/level of education, younger in age and earning lower income are likely to consume more of marine frozen fish species (P 〈 0.01) than others. 展开更多
关键词 Marine fish consumer preference consumption pattern Nigeria.
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Eukaryotic microbial distribution pattern and its potential effects on fisheries in the fish reserves of Qiantang River in breeding season
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作者 Hang LAI Li ZHAO +4 位作者 Wen YANG Regan NICHOLAUS Betina LUKWAMBE Jinyong ZHU Zhongming ZHENG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第2期566-581,共16页
To examine the eukaryotic biodiversity of aquatic ecosystems in the Qiantang River,China,eukaryotic microbes in the river were investigated using 18S rRNA gene sequencing during the breeding season(July to August 2018... To examine the eukaryotic biodiversity of aquatic ecosystems in the Qiantang River,China,eukaryotic microbes in the river were investigated using 18S rRNA gene sequencing during the breeding season(July to August 2018).Four distinct distribution patterns(1.Jiande;2.Tonglu and Fuyang;3.Jiubao;4.Yanguan)of the microbial community and their potential effects on fishery activities were observed.Results show lower abundances of Dinophyta and Fungi and higher abundances of Cryptophyta and Chlorophyta in Tonglu and Fuyang than those in the other three sections.In addition,the reserves(Tonglu and Fuyang)destabilized the original eukaryotic microbial co-occurrence network.Among all the environmental factors measured,nitrogen(nitrite,nitrate,ammonium),water temperature and total chlorophyll a acted as major driving factors that controlled the eukaryotic microbial distribution.Furthermore,the existence of some algae(e.g.,Chrysophyceae,Cryptophytes,and Chlorophyceae)and fungi(e.g.,Rhizophydium)in Tonglu and Fuyang was beneficial to juvenile fish growth and water quality,although some detrimental species(e.g.,Aphanomyces)needed attention.This study provides further insights into the sustainable protection and utilization of rivers. 展开更多
关键词 Qiantang River fish reserves 18s rRNA asymmetric eigenvector maps molecular ecological network analyses biological indicators
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On the origin of cardiac mucosa: A histological and immunohistoc-hemical study of cytokeratin expression patterns in the developing esophagogastric junction region and stomach
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作者 Gert De Hertogh Peter Van Eyken +1 位作者 Nadine Ectors Karel Geboes 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第29期4490-4496,共7页
AIM: To examine the fetal and neonatal esophagogastric junction region (EGJ) histologically for the presence of an equivalent to adult cardiac mucosa (CM); to study the expression patterns of all cytokeratins (C... AIM: To examine the fetal and neonatal esophagogastric junction region (EGJ) histologically for the presence of an equivalent to adult cardiac mucosa (CM); to study the expression patterns of all cytokeratins (CK) relevant to the EGJ during gestation; to compare the CK profile of the gestational and the adult EGJ; and to determine the degree of development in the adult EGJ histology and CK profile during gestation. METHODS: Forty-eight fetal autopsy specimens of the EGJ were step-sectioned and stained with hematoxylin and eosin (H&E) to select sections showing the mucosal lining. Immunohistochemistry for CK5, 7, 8, 13, 18, 19, and 20 was performed. Antibody staining was then graded for location, intensity, and degree. RESULTS: The distal esophagus was lined by simple columnar epithelium from 12-wk gestational age (GA). The proximal part of this segment consisted of mucusproducing epithelium, devoid of parietal cells. CK5 and 13 were present exclusively in multilayered epithelia and CK8, 18, and 19 predominantly in simple columnar epithelium. There were no differences in the frequencies of the coordinate CK7+/20+ and the CK7-/20- immunophenotypes between different locations. The prevalence of the CK7+/ 20- immunophenotype decreased, and that of the CK7-/ 20+ immunophenotype increased significantly from the distal esophagus to the distal stomach. CONCLUSION: Fetal columnar-lined lower esophagus (fetal CLE) may be the equivalent and precursor of the short segments of columnar epithelium found in the distal esophagus of some normal adult subjects. Esophageal simple columnar epithelium without parietal cells (ESN) may be the precursor of adult CM. The similarities between the fetal and adult EGJ and stomach CK expression pattems support the conclusion that adult CN has an identifiable precursor in the fetus. This would then indicate that at least a part of the adult CM has a congenital origin. 展开更多
关键词 Cardiac mucosa ORIGIN Fetal autopsy Barrett's CK7/20 pattern
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Patterns of international governance in the Arctic and China's approach
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作者 ZHAO Long 《Advances in Polar Science》 2016年第3期170-179,共10页
The process of rapid change in the Arctic is creating both opportunities and challenges. This paper highlights interactions between different actors in the Arctic in response to multidimensional environmental, politic... The process of rapid change in the Arctic is creating both opportunities and challenges. This paper highlights interactions between different actors in the Arctic in response to multidimensional environmental, political, commercial, and human challenges. It shows that international governance in the Arctic can be characterized by global, multilateral, and regional patterns derived from different mechanisms such as the Arctic Council or the Ilulissat declaration platform, and these interactions are based on common acknowledgment of challenges, mutual interests, and coordinated actions. The paper also examines China's participation in international governance in the Arctic. Distinguish from non-Arctic states in a general sense, China as an important stakeholder has both the rights and the capacity to be engaged in multilevel governance patterns. The substantive contribution of China's participation--an explorer in scientific cooperation, a pioneer promoting environmental protection, a potential consumer and investor in relation to economic opportunities, and a promoter of local development^are deeply interdepended with the future of development of three ~overnance patterns relatin~ to international ~overnance in the Arctic. 展开更多
关键词 ARCTIC governance patterns China's approach
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Patterns and Technology -- A Creative Approach to Isometries
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作者 Lucia Matos Isabel Cabrita 《Journal of Mathematics and System Science》 2012年第5期320-326,共7页
Today's math education basic syllabus gives an ever increasing emphasis to Geometry and Patterns. Curricula also advocate an approach that allows student to understand the concepts involved supported by dynamical com... Today's math education basic syllabus gives an ever increasing emphasis to Geometry and Patterns. Curricula also advocate an approach that allows student to understand the concepts involved supported by dynamical computer tools. However, there is not much research work joining these paradigms. Therefore, a case study was developed, with 9th grade students (14-15 years old), to evaluate the impact of a creative approach to isometries and symmetries-friezes, rosaceas (rosettes) and wallpapers-centered in patterns (reproduction, continuation, completion, description and creation) and using Geometer's Sketchpad software to solve, mainly in pairs, and discuss, with the whole class, the challenging tasks proposed, involving the formulation of hypothesis, argumentation and justification of the reasoning. The statistical analysis of the quantifiable data and content analysis of the qualitative data, collecting trough enquiry, direct observation and documental analysis (involving questionnaires, field notes, logbook, pre-tests and post-test, other works of the students including those computer related, and internal documents of the school) enable to conclude positively regarding the main research question underlying the study. In fact, it led to the conclusion that the teaching strategy implemented has contributed to deepen the student's knowledge and skills on geometry, mathematical communication and autonomy as well as to develop a closer relation with the field of geometry itself. This article focuses on one of the cases studied. The pair was selected due to be representative of most students and due to their communication skills. 展开更多
关键词 IsOMETRIEs patterns geometer's sketchpad mathematical creativity.
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Intraoperative Nerve Monitoring in Otolaryngology: A Survey of Clinical Practice Patterns
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作者 Stephanie Flukes Shane S. Ling +1 位作者 Travis Leahy Chady Sader 《International Journal of Otolaryngology and Head & Neck Surgery》 2013年第1期21-26,共6页
Introduction: Intraoperative nerve monitoring is used in otolaryngology to assist in identification of nerves at risk. It is hoped that this will lead to lower rates of nerve injury. The objective of this study was to... Introduction: Intraoperative nerve monitoring is used in otolaryngology to assist in identification of nerves at risk. It is hoped that this will lead to lower rates of nerve injury. The objective of this study was to quantify the use of monitoring technology in current clinical practice. Method: An electronic survey was distributed to 376 registered fellows of the Australian Society of Head and Neck Surgery. Results: One-hundred and twenty-five responses were obtained. The majority of respondents report using monitoring at least some of the time during thyroid, parotid, and mastoid surgery (80%, 87%, and 73% respectively). Predictors of use include experience with intraoperative monitoring during training, and high caseloads in parotid surgery. Practice setting did not predict use. Conclusion: Despite equivocal evidence that intraoperative nerve monitoring is associated with a reduction in nerve injuries, this study demonstrates that the technology is widely used amongst otolaryngologists. 展开更多
关键词 MONITORING INTRAOPERATIVE Mastoid/surgery Parotid Gland/surgery Thyroid Gland/surgery Physician’s Practice patterns
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Quantum Algorithm for Mining Frequent Patterns for Association Rule Mining
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作者 Abdirahman Alasow Marek Perkowski 《Journal of Quantum Information Science》 CAS 2023年第1期1-23,共23页
Maximum frequent pattern generation from a large database of transactions and items for association rule mining is an important research topic in data mining. Association rule mining aims to discover interesting corre... Maximum frequent pattern generation from a large database of transactions and items for association rule mining is an important research topic in data mining. Association rule mining aims to discover interesting correlations, frequent patterns, associations, or causal structures between items hidden in a large database. By exploiting quantum computing, we propose an efficient quantum search algorithm design to discover the maximum frequent patterns. We modified Grover’s search algorithm so that a subspace of arbitrary symmetric states is used instead of the whole search space. We presented a novel quantum oracle design that employs a quantum counter to count the maximum frequent items and a quantum comparator to check with a minimum support threshold. The proposed derived algorithm increases the rate of the correct solutions since the search is only in a subspace. Furthermore, our algorithm significantly scales and optimizes the required number of qubits in design, which directly reflected positively on the performance. Our proposed design can accommodate more transactions and items and still have a good performance with a small number of qubits. 展开更多
关键词 Data Mining Association Rule Mining Frequent pattern Apriori Algorithm Quantum Counter Quantum Comparator Grover’s search Algorithm
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黄褐棉45S rDNA的FISH定位及核型分析 被引量:5
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作者 吴琼 宋国立 +6 位作者 刘三宏 王春英 刘方 黎绍惠 张香娣 王玉红 王坤波 《植物遗传资源学报》 CAS CSCD 2008年第4期439-442,F0003,共5页
黄褐棉是棉属5个四倍体棉种之一,利用荧光原位杂交技术将45S rDNA定位在黄褐棉2、4、9号染色体,2号染色体上的45S rDNA特别大,信号位于随体并覆盖了染色体的短臂,比二倍体和四倍体棉种的45S rDNA都要大得多;另外的2对信号很小,形状与陆... 黄褐棉是棉属5个四倍体棉种之一,利用荧光原位杂交技术将45S rDNA定位在黄褐棉2、4、9号染色体,2号染色体上的45S rDNA特别大,信号位于随体并覆盖了染色体的短臂,比二倍体和四倍体棉种的45S rDNA都要大得多;另外的2对信号很小,形状与陆地棉中的弱信号类似。黄褐棉的核型公式为:2n=4x=52=50m(2SAT)+2sm,属于2B类型,第2对染色体为亚中着丝粒染色体,其余都为中部着丝粒染色体。黄褐棉的核型、随体数、45S rDNA与其他四倍体棉种区别很大,黄褐棉是一个非常特殊的四倍体棉种。 展开更多
关键词 黄褐棉 45s RDNA fish 核型
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植物45S rDNA的染色体位置的CPD染色和FISH分析 被引量:6
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作者 佘朝文 宋运淳 《广西植物》 CAS CSCD 北大核心 2008年第4期515-520,共6页
采用PI和DAPI组合(CPD)染色结合45SrDNA探针的荧光原位杂交(FISH)对分属6个科的16种植物的45S rDNA的染色体位置进行了分析。在所有供试植物中,共检测到53个45S rDNA位点。大多数45S rDNA位点分布在染色体的短臂;位于染色体臂内和染色... 采用PI和DAPI组合(CPD)染色结合45SrDNA探针的荧光原位杂交(FISH)对分属6个科的16种植物的45S rDNA的染色体位置进行了分析。在所有供试植物中,共检测到53个45S rDNA位点。大多数45S rDNA位点分布在染色体的短臂;位于染色体臂内和染色体末端的位点的比例大体相当;多数位于染色体臂内的45S rDNA位点有次缢痕形成,但rDNA重复单位簇所处的位置存在差异。根据45S rDNA所处的染色体臂的不同、距着丝粒远近的差异、形成次缢痕与否以及rDNA重复单位簇相对于次缢痕的位置等特征,将植物的45S rDNA位点划分为12种染色体分布类型。基于我们的结果和其他的报道对45S rDNA位点、核仁组织区(NOR)、次缢痕和随体相互之间的关系进行了分析。 展开更多
关键词 45s RDNA 核仁组织区 随体 次缢痕 CPD染色 荧光原位杂交(fish)
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16轮Blow-CAST-Fish的弱密钥攻击 被引量:2
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作者 孙晓玲 王美琴 +4 位作者 孙旭光 李忠 李姗姗 杨秋格 梁峰 《计算机工程与应用》 CSCD 北大核心 2011年第35期110-112,共3页
Blow-CAST-Fish的轮函数F由作为算法子密钥的四个S盒构成。如果S盒产生碰撞,则可构造F函数的输入差分为非零、输出差分为零的差分特征,进而对算法进行差分分析以获取其他子密钥。研究单个S盒的碰撞,构造F函数的差分特征,并测试使特征成... Blow-CAST-Fish的轮函数F由作为算法子密钥的四个S盒构成。如果S盒产生碰撞,则可构造F函数的输入差分为非零、输出差分为零的差分特征,进而对算法进行差分分析以获取其他子密钥。研究单个S盒的碰撞,构造F函数的差分特征,并测试使特征成立的弱密钥比例,给出了特征概率为2-49,弱密钥比例为2-52.4的14轮差分特征,并以此为基础,攻击16轮Blow-CAST-Fish。 展开更多
关键词 Blow-CAsT-fish 差分特征 弱密钥 轮函数 s
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低轮Blow-CAST-Fish算法的差分攻击 被引量:1
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作者 孙晓玲 王美琴 +5 位作者 李忠 孙旭光 李姗姗 杨秋格 曹桂荣 潘志安 《计算机工程》 CAS CSCD 2012年第12期99-101,共3页
对作为Blow-CAST-Fish算法子密钥的4个S盒的碰撞性进行分析,构造输入差分为非零、输出差分为零的轮函数F的差分特征,通过对算法进行差分分析,获取相关子密钥,并测试使特征成立的弱密钥概率。在此基础上,成功利用特征概率为2-61、弱密钥... 对作为Blow-CAST-Fish算法子密钥的4个S盒的碰撞性进行分析,构造输入差分为非零、输出差分为零的轮函数F的差分特征,通过对算法进行差分分析,获取相关子密钥,并测试使特征成立的弱密钥概率。在此基础上,成功利用特征概率为2-61、弱密钥概率为2-12的6轮差分特征攻击8轮Blow-CAST-Fish算法。 展开更多
关键词 Blow-CAsT-fish算法 差分攻击 差分特征 弱密钥 轮函数 s 碰撞
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白缘(鱼央)5S rDNA的扩增分析及其在染色体上的FISH定位
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作者 张伟伟 付元帅 +3 位作者 邵燕 王宝琴 石东里 张兰 《海洋学报》 CAS CSCD 北大核心 2016年第6期82-88,共7页
本文分别对雌雄白缘(鱼央)(鱼央)的5SrDNA进行了PCR扩增和序列分析,并采用双色荧光原位杂交(FISH)技术,以白缘(鱼央)的5SrDNA序列和小麦的45SrDNA为探针,对其在白缘(鱼央)雌雄中期染色体上进行了FISH定位研究。结果表明,白缘(鱼央)5SrDN... 本文分别对雌雄白缘(鱼央)(鱼央)的5SrDNA进行了PCR扩增和序列分析,并采用双色荧光原位杂交(FISH)技术,以白缘(鱼央)的5SrDNA序列和小麦的45SrDNA为探针,对其在白缘(鱼央)雌雄中期染色体上进行了FISH定位研究。结果表明,白缘(鱼央)5SrDNA序列无雌雄差异;5SrDNA的保守区序列为117bp;5SrDNA和45SrDNA分别被定位于白缘(鱼央)的性染色体和第5号染色体上。同时从GenBank中获得了22种鱼的5SrDNA,运用DNAman软件构建了23种鱼的系统发育树,对白缘(鱼央)的进化地位进行了初步研究。本研究为阐明白缘(鱼央)在鱼类系统进化中的位置、重复序列在脊椎动物性染色体上的分布状况以及与性别决定与分化的关系,提供了资料积累和分析依据。 展开更多
关键词 Liobagrus marginatus PCR 5s RDNA 系统进化树 染色体 fish
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