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An Attention-Based Neural Framework for Uncertainty Identification on Social Media Texts
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作者 Xu Han Binyang Li Zhuoran Wang 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第1期117-126,共10页
Uncertainty identification is an important semantic processing task. It is crucial to the quality of information in terms of factuality in many applications, such as topic detection and question answering. Factuality ... Uncertainty identification is an important semantic processing task. It is crucial to the quality of information in terms of factuality in many applications, such as topic detection and question answering. Factuality has become a premier concern especially in social media, in which texts are written informally. However, existing approaches that rely on lexical cues suffer greatly from the casual or word-of-mouth peculiarity of social media, in which the cue phrases are often expressed in substandard form or even omitted from sentences. To tackle these problems, this paper proposes an Attention-based Neural Framework for Uncertainty identification on social media texts, named ANFU. ANFU incorporates attention-based Long Short-Term Memory(LSTM) networks to represent the semantics of words and Convolutional Neural Networks(CNNs) to capture the most important semantics. Experiments were conducted on four datasets, including 2 English benchmark datasets used in the CoNLL-2010 task of uncertainty identification and 2 Chinese datasets of Weibo and Chinese news texts. Experimental results showed that our proposed ANFU approach outperformed the-state-of-the-art on all the datasets in terms of F1 measure. More importantly, 41.37% and 13.10% improvements were achieved over the baselines on English and Chinese social media datasets, respectively, showing the particular effectiveness of ANFU on social media texts. 展开更多
关键词 UNCERTAINTY IDENTIFICATION ATTENTION NEURAL networks SOCIAL media
Applications of advanced signal processing and machine learning in the neonatal hypoxic-ischemic electroencephalography 预览
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作者 Hamid Abbasi Charles P. Unsworth 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第2期222-231,共10页
Perinatal hypoxic-ischemic-encephalopathy significantly contributes to neonatal death and life-long disability such as cerebral palsy. Advances in signal processing and machine learning have provided the research comm... Perinatal hypoxic-ischemic-encephalopathy significantly contributes to neonatal death and life-long disability such as cerebral palsy. Advances in signal processing and machine learning have provided the research community with an opportunity to develop automated real-time identification techniques to detect the signs of hypoxic-ischemic-encephalopathy in larger electroencephalography/amplitude-integrated electroencephalography data sets more easily. This review details the recent achievements, performed by a number of prominent research groups across the world, in the automatic identification and classification of hypoxic-ischemic epileptiform neonatal seizures using advanced signal processing and machine learning techniques. This review also addresses the clinical challenges that current automated techniques face in order to be fully utilized by clinicians, and highlights the importance of upgrading the current clinical bedside sampling frequencies to higher sampling rates in order to provide better hypoxic-ischemic biomarker detection frameworks. Additionally, the article highlights that current clinical automated epileptiform detection strategies for human neonates have been only concerned with seizure detection after the therapeutic latent phase of injury. Whereas recent animal studies have demonstrated that the latent phase of opportunity is critically important for early diagnosis of hypoxic-ischemic-encephalopathy electroencephalography biomarkers and although difficult, detection strategies could utilize biomarkers in the latent phase to also predict the onset of future seizures. 展开更多
关键词 advanced signal processing AEEG automatic detection classification clinical EEG fetal HIE hypoxic-ischemic encephalopathy machine learning neonatal SEIZURE real-time identification review
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Species Diversity of Entomopathogenic Fungi Infecting the Sugarcane Aphid <i>Melanaphis sacchari</i>: A Recently Introduced Pest in Mexico 预览
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作者 Jorge Zambrano-Gutiérrez Raquel Alatorre-Rosas +4 位作者 María G. Carrillo-Benítez J. Refugio Lomelí-Flores Remigio A. Guzmán-Plazola Ausencio Azuara-Domínguez Antonio P. Terán-Vargas 《微生物学(英文)》 2019年第1期38-55,共18页
The sugarcane aphid, Melanaphis sacchari, is a key pest that affects sorghum in Mexico. During 2014 to 2016, in South of Tamaulipas sites and Bajio region in Guanajuato, the populations of this aphid were infected by ... The sugarcane aphid, Melanaphis sacchari, is a key pest that affects sorghum in Mexico. During 2014 to 2016, in South of Tamaulipas sites and Bajio region in Guanajuato, the populations of this aphid were infected by different species of Hypocrealean fungi. Based in the morphometric identification and molecular characterization, the species associated with sugarcane aphid in South of Tamaulipas were Lecanicillium longisporum, Beauveria bassiana and Isaria javanica. In this region, the higher infection levels were caused by L. longisporum, mortality range from 30.0% to 50.0%. The presence of I. javanica and B. bassiana represented less than 26.0% and 10.0%, respectively. In Guanajuato, the species found corresponded to L. longisporum and B. bassiana. The infection levels of both species in sugarcane aphid populations in Guanajuato sites were less than 1.00%. The natural occurrence of entomopathogenic fungi on sugarcane aphid populations was associated with climactic factors such as temperature and relative humidity and development of infections was possibly affected by abiotic factors such as crop phenological stage and applications of chemical insecticides realized by farmers for control of this aphid. Further studies on the ecology and physiology of these fungi and trials to determine virulence and persistence in M. sacchari populations are needed. This is the first report on natural presence of L. longisporum, B. bassiana and I. javanica causing disease on Melanaphis sacchari in Guanajuato and Tamaulipas, Mexico. 展开更多
关键词 APHID SORGHUM Hypocrealean Fungi Native Isolates Identification
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Verification of RFID System Usability in Silage Bale Life Cycle Management 预览
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作者 Katariina Penttila Antti Suokannas Ilpo P?l?nen 《农业科学与技术:A》 2019年第2期120-130,共11页
Digitalization has nowadays raised interest in variable applications of farming.Increase of knowledge level,by means of unique identification,automation and control,farmers gain relevant business profit.This research ... Digitalization has nowadays raised interest in variable applications of farming.Increase of knowledge level,by means of unique identification,automation and control,farmers gain relevant business profit.This research is focused on the utilization of passive radio frequency identification(RFID)technology in silage bale application,both manual and automated level.Challenges arise due to silage conservation,varying environmental and seasonal conditions,different identification environments and RFID operation principle.Further maximum communication signal strength is limited by telecommunication standard regulations(e.g.,ETSI).The applicability of RFID technology with different commercial passive transponders is measured manually in a silage bale of 160 cm in diameter,covering 360 degrees around the bale.In addition,automated field tests are conducted in a real environment,where the data collection system is appended to a tractor and RFID reader antenna in a baler.Manual measurements are conducted as identification distance(meters)and transponder population(number of tags),while automated measurements are based on the number of successfully identified silage bales.Based on the manual measurement results,the most suitable tags for the automated field measurements were chosen,and the applicability to silage bale identification was verified.Field tests showed 100%success,with 151/151 uniquely identified silage bales.Achieved results prove that passive RFID operates well enough in silage bale identification,further enabling the development of digitalization of silage bale life cycle. 展开更多
关键词 Digibale SILAGE BALE LIFE-CYCLE management radio frequency IDENTIFICATION DIGITALIZATION of SILAGE BALE unique IDENTIFICATION
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New few parameters differential evolution algorithm with application to structural identification
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作者 Rita Greco Ivo Vanzi 《交通运输工程学报(英文版)》 CSCD 2019年第1期1-14,共14页
Differential evolution algorithm(DEA)is a stochastic,population-based global optimization method.In this paper,we propose new schemes for both mutation and crossover operators in order to enhance the performances of t... Differential evolution algorithm(DEA)is a stochastic,population-based global optimization method.In this paper,we propose new schemes for both mutation and crossover operators in order to enhance the performances of the standard DEA.The advantage of these proposed operators is that they are'parameters-less',without a tuning phase of algorithm parameters that is often a disadvantage of DEA.Once the modified differential evolutions are presented,a large comparative analysis is performed with the aim to assess both correctness and efficiency of the proposed operators.Advantages of proposed DEA are used in an important task of modern structural engineering that is mechanical identification under external dynamic loads.This is because of the importance of using a“parametersless”algorithm in identification problems whose characteristics typically vary strongly case by case,needing of a continuous set up of the algorithm proposed.This important advantage of proposed optimizers,in front of other identification algorithms,is used to develop a computer code suitable for the automatic identification of a simple supported beam subject to an impact load,that has been tested both using numerical simulations and real standard tests dynamic.The results point out that this algorithm is an interesting candidate for standard applications in structural identification problems. 展开更多
关键词 DIFFERENTIAL evolution PARAMETRIC IDENTIFICATION STRUCTURAL IDENTIFICATION Optimization
注射剂微生物污染的RiboPrinter■微生物基因指纹系统鉴定及同源性分析
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作者 孙雪奇 秦力 +2 位作者 陈婕 费国琴 袁军 《华西药学杂志》 CAS CSCD 2019年第5期481-484,共4页
目的对注射剂的无菌检查阳性结果进行核糖体分型鉴定,并根据鉴定结果进行微生物污染的来源分析。方法采用RiboPrinter■微生物基因指纹系统对阳性菌A1和污染调查中采集菌株中的的16株葡萄球菌进行鉴定和同源性分析。结果 RiboPrinter■... 目的对注射剂的无菌检查阳性结果进行核糖体分型鉴定,并根据鉴定结果进行微生物污染的来源分析。方法采用RiboPrinter■微生物基因指纹系统对阳性菌A1和污染调查中采集菌株中的的16株葡萄球菌进行鉴定和同源性分析。结果 RiboPrinter■微生物基因指纹系统的鉴定结果与菌株的生化鉴定结果完全相同;A1的鉴定结果为科氏葡萄球菌,溯源自无菌检查实验的环境污染。结论基于核糖体分型原理的RiboPrinter■微生物基因指纹系统鉴定结果准确可靠,可用于鉴定及同源性分析污染的微生物。 展开更多
关键词 微生物污染 鉴定 同源性分析 葡萄球菌 RiboPrinter■微生物基因指纹系统 生化鉴定 阳性结果 无菌检查 相似系数
Location and Trajectory Identification from Microblogs
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作者 Na Ta Guo-Liang Li +1 位作者 Jun Hu Jian-Hua Feng 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第4期727-746,共20页
The rapid development of social networks has resulted in a proliferation of user-generated content(UGC),which can benefit many applications.In this paper,we study the problem of identifying a user's locations from... The rapid development of social networks has resulted in a proliferation of user-generated content(UGC),which can benefit many applications.In this paper,we study the problem of identifying a user's locations from microblogs,to facilitate effective location-based advertisement and recommendation.Since the location information in a microblog is incomplete,we cannot get an accurate location from a local microblog.As such,we propose a global location identification method,Glitter.Glitter combines multiple microblogs of a user and utilizes them to identify the user's locations.Glitter not only improves the quality of identifying a user's location but also supplements the location of a microblog so as to obtain an accurate location of a microblog.To facilitate location identification,Glitter organizes points of interest(POIs)into a tree structure where leaf nodes are POIs and non-leaf nodes are segments of POIs,e.g.,countries,cities,and streets.Using the tree structure,Glitter first extracts candidate locations from each microblog of a user which correspond to some tree nodes.Then Glitter aggregates these candidate locations and identifies top-κlocations of the user.Using the identified top-κuser locations,Glitter refines the candidate locations and computes top-κlocations of each microblog.To achieve high recall,we enable fuzzy matching between locations and microblogs.We propose an incremental algorithm to support dynamic updates of microblogs.We also study how to identify users'trajectories based on the extracted locations.We propose an effective algorithm to extract high-quality trajectories.Experimental results on real-world datasets show that our method achieves high quality and good performance,and scales well. 展开更多
关键词 LOCATION IDENTIFICATION microblog TRAJECTORY IDENTIFICATION
Study on the Identification of Original Plant and Crude Herbs in Paris daliensis H. Li et V.G. Souku and Paris dulongensis H. Li et S. Kuritap 预览
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作者 Risha WEIZE Zhongjie HUANG +3 位作者 Jixiu SHEN Xuexue LI Zhengming YANG Yuan LIU 《药用植物研究(英文版)》 2019年第2期54-57,共4页
[Objectives] Via systematic comparative study on Paris daliensis and Paris dulongensis, the research aimed to provide test data for their character and microscopic identification.[Methods] Original plants, characters,... [Objectives] Via systematic comparative study on Paris daliensis and Paris dulongensis, the research aimed to provide test data for their character and microscopic identification.[Methods] Original plants, characters, microscopic identification of cross section and powder of rhizome were used.[Results] Microscopic characteristics of cross section and powder of rhizome were basically consistent with identification results of literature, and parenchyma cell of P. dulongensis had brown-red mass.[Conclusions] The research could provide reference basis for identification of authenticity and establishment of quality standards for original plants and medicinal materials of P. daliensis and P. dulongensis, and their further research and development. 展开更多
关键词 PARIS daliensis PARIS dulongensis Character IDENTIFICATION MICROSCOPIC IDENTIFICATION
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Pharmacognosy Identification of Xiaohuangcao ( Dendrobium loddigesi Rolfe) 预览
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作者 Miao ZHANG Li LI +3 位作者 Jianbei TENG Hua ZHU Zhonghua DAI Long CHEN 《农业生物技术:英文版》 CAS 2019年第3期177-179,共3页
[Objectives]Pharmacognosy identification was performed on Xiaohuangcao ( Dendrobium loddigesi Rolfe).[Methods]The medicinal materials were identified through original plants,characters,microscopic structure and thin-l... [Objectives]Pharmacognosy identification was performed on Xiaohuangcao ( Dendrobium loddigesi Rolfe).[Methods]The medicinal materials were identified through original plants,characters,microscopic structure and thin-layer identification characteristics.[Results]D.loddigesi has obvious plant morphology,characters,microscopic structure and thin-layer identification characteristics.The stem of Xiaohuangcao is slender and cylindrical,and the surface is golden yellow;and the fiber bundles outside the vascular bundles are crescent-shaped or semi-circular in the stem transection.For the powder,crystal fiber can be observed;the vascular bundles are embedded with siliceous block cells;and there are more starch grains.In the thin layer chromatography,petroleum ether-ethyl acetate-butanone-glacial acetic acid (8.5∶ 3.5∶ 1.5∶ 5 d) was used as a developing solvent,and 10% sulfuric acid ethanol solution was used as a color developing agent.[Conclusions]The research results provide reference for the application of the medicinal material and the formulation of its related quality standards. 展开更多
关键词 DENDROBIUM loddigesi Rolfe CHARACTER IDENTIFICATION MICROSCOPIC IDENTIFICATION THIN-LAYER chromatography
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Identification of Microplankton in South China Sea with Image-Matching Individual PCR 预览
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作者 LI Si YANG Guanpin +1 位作者 ZHU Baohua PAN Kehou 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第1期219-226,共8页
In this study,marine microplankton were identified by combining standard light microscopy with Sanger 18S rRNA gene sequencing.The image-matching individual PCR technique was applied to identify the image collectable ... In this study,marine microplankton were identified by combining standard light microscopy with Sanger 18S rRNA gene sequencing.The image-matching individual PCR technique was applied to identify the image collectable unicellular microplankton to genera.Instead of pure strain culture and morphological identification,microplankton individual cells were isolated and fixed with glutaraldehyde,frozen and stored for months.Finally,they were imaged under a microscope and molecularly identified via phylogenetic analysis of their 18S ribosomal RNA gene(18S rDNA).Microplankton cells were collected at 30 locations in South China Sea,and were assigned to 21 known and 4 unidentified genera(2 uncultured fungi and 2 uncultured stramenopiles)with phylogenetic analysis in parallel to the morphological identification. 展开更多
关键词 image-matching INDIVIDUAL PCR MICROPLANKTON 18S ribosomal RNA gene morphological IDENTIFICATION molecular IDENTIFICATION South China Sea
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Development and Modeling of Remotely Operated Scaled Multi-wheeled Combat Vehicle Using System Identification
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作者 A.N.Ouda Amr Mohamed +2 位作者 Moustafa EI-Gindy Haoxiang Lang Jing Ren 《国际自动化与计算杂志:英文版》 EI CSCD 2019年第3期261-273,共13页
This paper describes the development and modeling of a remotely operated scaled multi-wheeled combat vehicle(ROMWCV)using system identification methodology for heading angle tracking.The vehicle was developed at the v... This paper describes the development and modeling of a remotely operated scaled multi-wheeled combat vehicle(ROMWCV)using system identification methodology for heading angle tracking.The vehicle was developed at the vehicle dynamics and crash research(VDCR)Lab at the University of Ontario Institute of Technology(UOIT)to analyze the characteristics of the full-size model.For such vehicles,the development of controllers is considered the most crucial issue.In this paper,the ROMWCV is developed first.An experimental test was carried out to record and analyze the vehicle input/output signals in open loop system,which is considered a multi-input-single-output(MISO)system.Subsequently,a fuzzy logic controller(FLC)was developed for heading angle tracking.The experiments showed that it was feasible to represent the dynamic characteristics of the vehicle using the system identification technique.The estimation and validation results demonstrated that the obtained identified model was able to explain 88.44%of the output variation.In addition,the developed FLC showed a good heading angle tracking. 展开更多
关键词 Autonomous multi-wheeled VEHICLE system IDENTIFICATION all wheel STEERING fuzzy logic(FL) PARAMETRIC IDENTIFICATION
基于先验知识的香烟防伪数字串识别 预览
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作者 彭召 丁晓 +2 位作者 刘哲 陈衡 刘凯 《计算机应用与软件》 北大核心 2019年第12期189-194,244,共7页
香烟防伪数字串对于随机抽取市场香烟防伪数字并批量鉴别香烟真伪十分重要。针对香烟防伪鉴定实际需求,提出一种新的数字串识别方法。采用目标检测算法,定位出大概数字串区域的最小外接矩形;将最小外接矩形分割,将分割得到的小矩形图片... 香烟防伪数字串对于随机抽取市场香烟防伪数字并批量鉴别香烟真伪十分重要。针对香烟防伪鉴定实际需求,提出一种新的数字串识别方法。采用目标检测算法,定位出大概数字串区域的最小外接矩形;将最小外接矩形分割,将分割得到的小矩形图片分类,判断分类结果是否满足先验知识。如果不满足,则调整外接矩形参数,重复以上分割识别过程,直到找到满足要求的矩形,并把此时的分类结果作为最终识别结果。实验结果表明,该方法较好地满足了香烟鉴定的需求。 展开更多
关键词 鉴别 定位 分割 香烟鉴定
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Molecular Identification of <i>Campylobacter</i>Species from Positive Cultural Stool Samples of Diarrhoeic Children in Osun State 预览
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作者 O. C. Adekunle A. A. Onilude T. O. Sanusi 《医学微生物学(英文)》 2019年第1期8-15,共8页
Death of infants from diarrhoea is a common occurrence in sub-Saharan Africa. This is attributed to unhygienic practices which aid the proliferation of diarrhoea-causing microorganisms. Among these microorganisms, Cam... Death of infants from diarrhoea is a common occurrence in sub-Saharan Africa. This is attributed to unhygienic practices which aid the proliferation of diarrhoea-causing microorganisms. Among these microorganisms, Cam- pylobacter species have been reported as one of the causal agents, Campylobacter spp. are human intestinal pathogens of global importance and their pathogenicity mechanisms are not well understood. This study was designed to investigate the molecular characterisation of Campylobacter gotten from cultural methods in Osun State. Campylobacters isolated were biochemically characterized and biotyped. Confirmation of Campylobacter was done using flaA gene, hippuricase O for Campylobacter jejuni and aspartokinase gene for Campylobacter coli and single locus sequencing glnA gene were performed by PCR. Twenty five samples were amplified by PCR out of 57 Campylobacter strains that were positive for cultural methods from 815 stool samples with diarrhoea and 100 stool samples without diarrhoea. No Campylobacter was isolated from stools of children in the control group. Twenty-five isolates comprising of 18 Campylobater jejuni and 7 C. coli were identified. The nucleotide sequence of the gln A for all the isolated Campylobacter spp. showed 91.0% similarity with the ones in the GenBank. The C. jejuni was classified into biotypes I (44.4%) and II (55.6%) and all C. coli were of biotype I. 展开更多
关键词 Campylobacters Genes Culture POLYMERASE Chain Reaction (PCR) Identification
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苦瓜平脐蠕孢叶斑病病原鉴定
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作者 秦健 黄如葵 +7 位作者 陈振东 刘杏连 梁家作 陈小凤 黄熊娟 黄玉辉 冯诚诚 琚茜茜 《植物病理学报》 CAS CSCD 北大核心 2019年第5期711-714,共4页
苦瓜是葫芦科苦瓜属植物,在亚洲热带地区、东非、加勒比海等地区均有种植,是药食兼用的重要蔬菜,也是广西南菜北运的主要蔬菜品种[1,2]。据农业部门不完全统计,广西苦瓜的生产面积超过1.6万公顷,且逐年有增加的趋势。近年来,随着气候的... 苦瓜是葫芦科苦瓜属植物,在亚洲热带地区、东非、加勒比海等地区均有种植,是药食兼用的重要蔬菜,也是广西南菜北运的主要蔬菜品种[1,2]。据农业部门不完全统计,广西苦瓜的生产面积超过1.6万公顷,且逐年有增加的趋势。近年来,随着气候的变化,作物栽培面积的扩大,病害的发生也在不断增加。 展开更多
关键词 BITTER gourd LEAF SPOT disease identification BIPOLARIS BICOLOR
尺蛾科昆虫性信息素组分特征及应用进展 预览
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作者 马涛 黄志嘉 +4 位作者 朱映 林娜 肖强 何余容 温秀军 《林业科学》 EI CAS CSCD 北大核心 2019年第5期152-162,共11页
国内外对于鳞翅目昆虫性信息素的研究最为详细。本文阐述鳞翅目昆虫性信息素活性组分的最新分类进展,根据其化学结构可分为TypeⅠ、TypeⅡ、TypeⅢ、Type 0 4类。其中:Type I为分子结构具有末端功能团的C10-C18醇、醛、醋酸酯类化合物,... 国内外对于鳞翅目昆虫性信息素的研究最为详细。本文阐述鳞翅目昆虫性信息素活性组分的最新分类进展,根据其化学结构可分为TypeⅠ、TypeⅡ、TypeⅢ、Type 0 4类。其中:Type I为分子结构具有末端功能团的C10-C18醇、醛、醋酸酯类化合物,分布于多个鳞翅目总科中; TypeⅡ为C17-C23的不饱和碳氢化合物以及相对应的环氧衍生物,广泛分布于尺蛾总科中; TypeⅢ为携带1个或多个甲基分支的C17-C23化合物,仅出现在少数的鳞翅目昆虫中;而Type 0为与植物挥发物结构类似的短链仲醇或酮类化合物,分布于进化上较为原始的昆虫中。尺蛾总科作为鳞翅目昆虫的第三大科,目前共计93属158种尺蛾的性信息素组分得到鉴定,其性信息素组分中除了姬尺蛾亚科以TypeⅠ为主以外,灰尺蛾亚科、尺蛾亚科、沙尺蛾亚科、花尺蛾亚科、星尺蛾亚科均是以TypeⅡ为主。尺蛾科昆虫性信息素组分碳链较长,结构复杂,多数为不饱和烃类化合物(TypeⅡ型),严重影响了全球尺蛾类性信息素组分的化学鉴定及野外应用,通过分析对已鉴定的尺蛾性信息素组分及结构特征,明确其性信息素组分化合物的双键位置、环氧结构和手性构象,以及在各亚科、属、种之间的分布特征,并探讨我国重要尺蛾(茶尺蠖、国槐尺蠖、银花尺蠖、油桐尺蠖、春尺蠖等)的性信息素研究情况,可为今后鉴定未知尺蛾性信息素活性组分,以及利用昆虫性信息素对尺蛾类害虫进行有效的绿色防控等提供参考。 展开更多
关键词 尺蛾 性信息素 鉴定 应用进展
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当代大学生对“红船精神”的认同研究——基于浙江农林大学学生的实证研究 预览
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作者 崔雨晴 《教育信息化论坛》 2019年第3期26-28,共3页
通过整理分析大学生对首创精神、坚定理想、奋斗精神为内涵的"红船精神"的认同情况,探讨了对"红船精神"认知高分组的学生的基本特征,同时分析认知分数高但实践行为低分的学生的基本特征,得出结论并提出相关建议。
关键词 大学生 红船精神 首创精神 奋斗精神 奉献精神
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基于精细DEM的崩塌滑坡灾害识别及主控因素分析--以雅鲁藏布江缝合带加查--朗县段为例 预览
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作者 王瑞琪 王学良 +3 位作者 刘海洋 孙娟娟 王新辉 张苏 《工程地质学报》 CSCD 北大核心 2019年第5期1146-1152,共7页
雅鲁藏布江缝合带加查-朗县段位于青藏高原东南部地区,地形起伏度大,地质灾害分布密集。本文主要基于机载雷达获取的10 m精度影像数据,卫星遥感数据,以及高精度无人机航拍数据,对崩塌、滑坡地质灾害进行识别,并研究其主控因素。共计识... 雅鲁藏布江缝合带加查-朗县段位于青藏高原东南部地区,地形起伏度大,地质灾害分布密集。本文主要基于机载雷达获取的10 m精度影像数据,卫星遥感数据,以及高精度无人机航拍数据,对崩塌、滑坡地质灾害进行识别,并研究其主控因素。共计识别41处崩塌与92处滑坡,利用统计方法,分析崩塌、滑坡与各主控因素的相关性。对于识别的崩塌滑坡进行厚度识别,从而建立了灾害面积与体积之间的函数关系,实现了在已知崩塌滑坡灾害面积的情况下,对灾害规模的估算。本文阐明了区内地质灾害的空间分布情况,并研究了区域内崩塌滑坡地质灾害的主控因素。结果表明:滑坡主要发育在雅鲁藏布江南岸以及北岸坡体的中下部,而崩塌主要发生在北岸坡体的中上部。地层岩性、地形地貌、地质构造和岩体结构是崩塌、滑坡的主控因素,崩塌主要集中在砾岩和花岗岩地区,而千枚岩地区多发育有滑坡灾害。研究区内的崩塌由坡度、坡向和高程共同控制,其中坡度为主控因素;滑坡主要受到断层的控制,坡度对滑坡的发育具有一定的影响作用,高程和坡向对滑坡的影响较小。滑坡主要以牵引型为主,且大多数滑坡滑动的方向大致垂直于断裂的走向;崩塌主要以滑移式为主,通过对岩体结构面的提取可以分析其结构面发育情况,从而分析结构面对崩塌的控制作用。 展开更多
关键词 地质灾害 识别 主控因素 相关性分析
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萱草花类黄酮提取、分析及其抗氧化性研究 预览
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作者 于海燕 解铜 +4 位作者 钱新华 田怀香 陈臣 张志国 邹维娜 《食品工业科技》 CAS 北大核心 2019年第21期179-185,共7页
为了开发利用萱草花资源,在萱草花类黄酮超声辅助提取工艺优化的基础上,利用高效液相色谱法分析了萱草花中类黄酮组分,并对不同品种萱草花的抗氧化性进行了分析。结果表明:萱草花类黄酮超声辅助提取最佳工艺条件为乙醇体积分数75%,超声... 为了开发利用萱草花资源,在萱草花类黄酮超声辅助提取工艺优化的基础上,利用高效液相色谱法分析了萱草花中类黄酮组分,并对不同品种萱草花的抗氧化性进行了分析。结果表明:萱草花类黄酮超声辅助提取最佳工艺条件为乙醇体积分数75%,超声功率198 W,超声时间23 min,在此条件下萱草花类黄酮提取率为91.15%;萱草花中含有儿茶素、表儿茶素、芦丁、异槲皮素和柚皮素,其中芦丁是萱草花中含量最多的类黄酮;“杜鹃”、“极地之光”和“火凤凰”三个品种的萱草花均具有较好的抗氧化性,以DPPH自由基清除率和·OH清除率为指标其等效VC当量分别为10.88、24.22、17.55 mg/g(干重)和41.97、38.02、35.38 mg/g(干重)。本研究表明萱草花富含生物活性成分和抗氧化能力。 展开更多
关键词 萱草花 类黄酮 提取 鉴定 抗氧化 高效液相色谱
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工业生产中工业互联网标识解析技术应用研究 预览
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作者 曾鹏 刘阳 《自动化博览》 2019年第11期46-48,共3页
标识解析技术在重要产品追溯及物流领域已经取得了成功,但是在工业互联网中的生产制造环节应用仍有一定局限性。通过对工业生产全过程标识技术应用现状的分析,基于语义化技术提出了适用于工业生产的标识解析应用系统,以支撑跨企业、跨... 标识解析技术在重要产品追溯及物流领域已经取得了成功,但是在工业互联网中的生产制造环节应用仍有一定局限性。通过对工业生产全过程标识技术应用现状的分析,基于语义化技术提出了适用于工业生产的标识解析应用系统,以支撑跨企业、跨行业以及跨区域的工业互联网综合应用。 展开更多
关键词 标识解析 工业互联网 工业生产 语义
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铁棒锤种子蛋白质提取及聚丙烯酰胺凝胶电泳研究 预览
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作者 陆国弟 杨扶德 +3 位作者 陈红刚 王惠珍 杜弢 邢豪 《中国中医药信息杂志》 CAS CSCD 2019年第6期64-69,共6页
目的构建适合铁棒锤种子蛋白质研究的聚丙烯酰胺凝胶电泳(SDS-PAGE)体系,为铁棒锤种子纯度检测及鉴别研究提供技术支撑。方法采用6种蛋白质提取法提取伏毛铁棒锤种子蛋白质,并筛选出最佳提取方法,在此基础上研究不同分离胶浓度、料液比... 目的构建适合铁棒锤种子蛋白质研究的聚丙烯酰胺凝胶电泳(SDS-PAGE)体系,为铁棒锤种子纯度检测及鉴别研究提供技术支撑。方法采用6种蛋白质提取法提取伏毛铁棒锤种子蛋白质,并筛选出最佳提取方法,在此基础上研究不同分离胶浓度、料液比、上样量对伏毛铁棒锤种子蛋白电泳分离效果的影响,并采用筛选出的蛋白质最佳提取分离方法对铁棒锤和伏毛铁棒锤种子进行鉴定。结果巯基乙醇法提取的伏毛铁棒锤种子蛋白质电泳图谱效果较佳,电泳谱带数最多(14条)、最清晰,适合于其种子纯度检测;分离胶浓度为15%、料液比为1∶10(M/V)、蛋白上样量稀释5倍时,其种子蛋白质电泳分离效果较好;铁棒锤和伏毛铁棒锤种子蛋白质电泳图谱在蛋白质谱带位置和强弱上有一定差异。结论本研究建立的铁棒锤种子蛋白样品制备方法及SDS-PAGE技术可用于铁棒锤种子纯度检测,其蛋白质图谱可作为铁棒锤与伏毛铁棒锤种子的鉴别依据。 展开更多
关键词 铁棒锤 种子 聚丙烯酰胺凝胶电泳 蛋白质提取 鉴定
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