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Joint salient object detection and existence prediction
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作者 Huaizu JIANG Ming-Ming CHENG +2 位作者 Shi-Jie LI Ali BORJI Jingdong WANG 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第4期778-788,共11页
Recent advances in supervised salient object detection modeling has resulted in significant performance improvements on benchmark datasets. However, most of the existing salient object detection models assume that at ... Recent advances in supervised salient object detection modeling has resulted in significant performance improvements on benchmark datasets. However, most of the existing salient object detection models assume that at least one salient object exists in the input image. Such an assumption often leads to less appealing saliency maps on the background images with no salient object at all. Therefore, handling those cases can reduce the false positive rate of a model. In this paper, we propose a supervised learning approach for jointly addressing the salient object detection and existence prediction problems. Given a set of background-only images and images with salient objects, as well as their salient object annotations, we adopt the structural SVM framework and formulate the two problems jointly in a single integrated objective function: saliency labels of superpixels are involved in a classification term conditioned on the salient object existence variable, which in turn depends on both global image and regional saliency features and saliency labels assignments. The loss function also considers both image-level and regionlevel mis-classifications. Extensive evaluation on benchmark datasets validate the effectiveness of our proposed joint approach compared to the baseline and state-of-the-art models. 展开更多
关键词 salient object DETECTION EXISTENCE PREDICTION JOINT INFERENCE SALIENCY DETECTION
Aircraft engine fault detection based on grouped convolutional denoising autoencoders
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作者 Xuyun FU Hui LUO +1 位作者 Shisheng ZHONG Lin LIN 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第2期296-307,共12页
Many existing aircraft engine fault detection methods are highly dependent on performance deviation data that are provided by the original equipment manufacturer. To improve the independent engine fault detection abil... Many existing aircraft engine fault detection methods are highly dependent on performance deviation data that are provided by the original equipment manufacturer. To improve the independent engine fault detection ability, Aircraft Communications Addressing and Reporting System(ACARS) data can be used. However, owing to the characteristics of high dimension, complex correlations between parameters, and large noise content, it is difficult for existing methods to detect faults effectively by using ACARS data. To solve this problem, a novel engine fault detection method based on original ACARS data is proposed. First, inspired by computer vision methods, all variables were divided into separated groups according to their correlations. Then, an improved convolutional denoising autoencoder was used to extract the features of each group. Finally, all of the extracted features were fused to form feature vectors. Thereby, fault samples could be identified based on these feature vectors. Experiments were conducted to validate the effectiveness and efficiency of our method and other competing methods by considering real ACARS data as the data source. The results reveal the good performance of our method with regard to comprehensive fault detection and robustness. Additionally, the computational and time costs of our method are shown to be relatively low. 展开更多
关键词 Aircraft engines ANOMALY DETECTION Convolutional NEURAL Network(CNN) DENOISING autoencoder Engine health management FAULT DETECTION
动物源细胞外基质中糖胺聚糖物质的检测方法 预览
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作者 张伟 陈俊霖 胡康 《中国组织工程研究》 CAS 北大核心 2019年第30期4861-4867,共7页
背景:作为每个组织和器官中的细胞分泌产物,细胞外基质凭借其独一无二的生物学特性成为了临床应用中一种独特的再生型生物材料。糖胺聚糖作为细胞外基质中的重要活性物质之一,具有诸多优良的生物学特性。目的:整理总结近年来国内外对细... 背景:作为每个组织和器官中的细胞分泌产物,细胞外基质凭借其独一无二的生物学特性成为了临床应用中一种独特的再生型生物材料。糖胺聚糖作为细胞外基质中的重要活性物质之一,具有诸多优良的生物学特性。目的:整理总结近年来国内外对细胞外基质中糖胺聚糖检测方法的研究进展,并对各方法进行了对比,为优化细胞外基质糖胺聚糖检测方法提供帮助和方法参考。方法:通过输入关键词“糖胺聚糖检测、细胞外基质、determination methods of glycosaminoglycan、Animal-derived extracellular matrix”,从PubMed、知网等文献搜索引擎共搜索出2 037篇相关文献,筛选并整理63篇文献,总结出常见的糖胺聚糖检测方法。根据阅读文献时总结的思路,提出基于现有提取检测糖胺聚糖方法的改进方案,并设计对比实验验证。结果与结论:糖胺聚糖对动物源细胞外基质生物学性能起着至关重要的作用,可赋予细胞外基质材料及产品优异的生物活性与促修复功能。检测材料中糖胺聚糖含量可指导细胞外基质材料的工艺优化,因此糖胺聚糖检测方法至关重要。目前糖胺聚糖的检测方法主要有高效液相色谱法、糖醛酸分析法、乙醣胺定量分析法与二甲基亚甲基蓝检测法,以上方法均存在一定的局限性。基于已有的研究成果,针对二甲基亚甲基蓝检测法中的样本消化、糖胺聚糖提取等步骤做了改进,大幅度提升了检测结果的准确度,为其他糖胺聚糖检测方法提供了思路和参考。 展开更多
关键词 细胞外基质 糖胺聚糖 临床应用 检测方法 生物学特性 制作工艺 二甲基亚甲基蓝检测 高效液相色谱法
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Unsupervised Electric Motor Fault Detection by Using Deep Autoencoders 预览
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作者 Emanuele Principi Damiano Rossetti +1 位作者 Stefano Squartini Francesco Piazza 《自动化学报:英文版》 CSCD 2019年第2期441-451,共11页
Fault diagnosis of electric motors is a fundamental task for production line testing, and it is usually performed by experienced human operators. In the recent years, several methods have been proposed in the literatu... Fault diagnosis of electric motors is a fundamental task for production line testing, and it is usually performed by experienced human operators. In the recent years, several methods have been proposed in the literature for detecting faults automatically. Deep neural networks have been successfully employed for this task, but, up to the authors’ knowledge, they have never been used in an unsupervised scenario. This paper proposes an unsupervised method for diagnosing faults of electric motors by using a novelty detection approach based on deep autoencoders. In the proposed method, vibration signals are acquired by using accelerometers and processed to extract LogMel coefficients as features. Autoencoders are trained by using normal data only, i.e., data that do not contain faults. Three different autoencoders architectures have been evaluated: the multilayer perceptron(MLP) autoencoder, the convolutional neural network autoencoder, and the recurrent autoencoder composed of long short-term memory(LSTM) units. The experiments have been conducted by using a dataset created by the authors, and the proposed approaches have been compared to the one-class support vector machine(OC-SVM) algorithm. The performance has been evaluated in terms area under curve(AUC) of the receiver operating characteristic curve, and the results showed that all the autoencoder-based approaches outperform the OCSVM algorithm. Moreover, the MLP autoencoder is the most performing architecture, achieving an AUC equal to 99.11 %. 展开更多
关键词 Autoencoder convolutional NEURAL NETWORKS electric motor fault DETECTION long short-term memory NEURAL NETWORKS NOVELTY DETECTION
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Research on Low Energy Consumption Distributed Fault Detection Mechanism in Wireless Sensor Network 预览
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作者 Shuang Jia Lin Ma Danyang Qin 《中国通信:英文版》 SCIE CSCD 2019年第3期179-189,共11页
Wireless sensor network is an important technical support for ubiquitous communication.For the serious impacts of network failure caused by the unbalanced energy consumption of sensor nodes,hardware failure and attack... Wireless sensor network is an important technical support for ubiquitous communication.For the serious impacts of network failure caused by the unbalanced energy consumption of sensor nodes,hardware failure and attacker intrusion on data transmission,a low energy consumption distributed fault detection mechanism in wireless sensor network(LEFD)is proposed in this paper.Firstly,the time correlation information of nodes is used to detect fault nodes in LEFD,and then the spatial correlation information is adopted to detect the remaining fault nodes,so as to check the states of nodes comprehensively and improve the efficiency of data transmission.In addition,the nodes do not need to exchange information with their neighbor nodes in the initial detection process since LEFD adopts the data sensed by node itself to detect some types of faults,thus reducing the energy consumption of nodes effectively.Finally,LEFD also considers the nodes that may have transient faults.Performance analysis and simulation results show that the proposed detection mechanism can improve the transmission performance and reduce the energy consumption of network effectively. 展开更多
关键词 wireless sensor network low energy CONSUMPTION FAULT DETECTION DETECTION ACCURACY
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Effect of Endocuff use on colonoscopy outcomes:A systematic review and meta-analysis 预览
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作者 Konstantinos Triantafyllou Paraskevas Gkolfakis +3 位作者 Georgios Tziatzios Ioannis S Papanikolaou Lorenzo Fuccio Cesare Hassan 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第9期1158-1170,共13页
BACKGROUND Endocuff-a plastic device with flexible projections-mounted on the distal tip of the colonoscope,promises improved colonic mucosa inspection.AIM To elucidate the effect of Endocuff on adenoma detection rate... BACKGROUND Endocuff-a plastic device with flexible projections-mounted on the distal tip of the colonoscope,promises improved colonic mucosa inspection.AIM To elucidate the effect of Endocuff on adenoma detection rate(ADR),advanced ADR(AADR)and mean number of adenomas per colonoscopy(MAC).METHODS Literature searches identified randomized-controlled trials evaluating Endocuffassisted colonoscopy(EAC)vs conventional colonoscopy(CC)in terms of ADR,AADR and MAC.The effect size on study outcomes was calculated using fixed or random effect model,as appropriate,and it is shown as relative risk(RR)[95%confidence interval(CI)]and mean difference(MD)(95%CI).The rate of device removal in EAC arms was also calculated.RESULTS We identified nine studies enrolling 6038 patients.All studies included mixed population(screening,surveillance and diagnostic examinations).Seven and two studies evaluated the first and the second-generation device,respectively.EAC was associated with increased ADR compared to CC[RR(95%CI):1.18(1.05-1.32);Ι^2=71%];EAC benefits more endoscopists with ADR≤35%compared to those with ADR>35%[RR(95%CI):1.37(1.08-1.74);Ι^2=49%vs 1.10(0.99-1.24);Ι^2=71%].In terms of AADR and MAC,no difference was detected between EAC and CC[RR(95%CI):1.03(0.85-1.25);Ι^2=15%and MD(95%CI):0.30(-0.17-0.78);Ι^2=99%].Subgroup analysis did not show any difference between the two device generations regarding all three endpoints.In EAC arms,the device had to be removed in 3%(95%CI:2%-5%)of the cases mainly due to tortuous sigmoid or presence of diverticula along it.CONCLUSION EAC increases ADR compared to CC,especially for endoscopists with lower ADR.On the other hand,no significant effect on AADR and MAC was detected. 展开更多
关键词 ADENOMA DETECTION rate COLONOSCOPY ADENOMA DETECTION Endocuff Endocuff-Vision
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Fluorescent probe gold nanodots to quick detect Cr(VI) via oxidoreduction quenching process
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作者 Yueqi Zhao Yuanqing Sun +7 位作者 Yingnan Jiang Shanliang Song Tianxin Zhao Yue Zhao Xinyu Wang Baoquan Li Bai Yang Quan Lin 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第1期133-141,共9页
A method is described here for the quickly(<30 s) accurate determination of Cr(Ⅵ)(Cr2O72-), based on fluorescent probes gold nanodots(AuNDs, excitation/emission peaks at 395/604 nm) coated with glutathione(GSH). T... A method is described here for the quickly(<30 s) accurate determination of Cr(Ⅵ)(Cr2O72-), based on fluorescent probes gold nanodots(AuNDs, excitation/emission peaks at 395/604 nm) coated with glutathione(GSH). The fluorescence of the AuNDs responses linearly to Cr(Ⅵ) concentrations, ranging widely from 1 nM to 10 m M with detection limit as low as 0.35 nM. At the same time, the AuNDs is demonstrated highly selective for Cr(Ⅵ) detection over other acid group ions and metal ions without any masking reagent. These make probability for practical use. The quenching mechanism is investigated deeply via fluorescent lifetime, XPS and TEM analysis. Different from most reported quenching explanation of aggregation derived from charge attraction, these results verify the redox reaction between Cr2O72-and sulfhydryl(–S) of GSH. The Au(Ⅰ)–S bonds of AuNDs broke, accompanies with the oxidation of –S to form S–S bonds. As a result, AuNDs cross linked to each other. In the end, the fluorescence quenched. Attractively, the present study provides a new strategy for pollutant detection, such as from harmful Cr(Ⅵ) of Cr2O72-to nontoxic Cr(Ⅲ). 展开更多
关键词 fluorescent probe of Cr (Ⅵ) Au NANODOTS quick and quantitative DETECTION fluorescence QUENCHING mechanism POLLUTANT DETECTION
Lattice reduction aided belief propagation for massive MIMO detection
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作者 Senjie ZHANG Zhiqiang HE +2 位作者 Kai NIU Shi JIN Hong CHENG 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第4期123-135,共13页
Efficient massive MIMO detection for practical deployment, which is with spatially correlated channel and high-order modulation, is a challenging topic for the fifth generation mobile communication(5G). In this paper,... Efficient massive MIMO detection for practical deployment, which is with spatially correlated channel and high-order modulation, is a challenging topic for the fifth generation mobile communication(5G). In this paper, lattice reduction aided belief propagation(LRA-BP) is proposed for massive MIMO detection. LRA-BP applies the message updating rules of Markov random field based belief propagation(MRF-BP) in lattice reduced MIMO system. With the lattice reduced, well-conditioned MIMO channel,LRA-BP obtains better message updating and detection performance in spatially correlated channel than MRF-BP. Log-domain arithmetic is used in LRA-BP for computational complexity reduction. Simulation result shows that LRA-BP outperforms MRF-BP with 3–10 dB in terms of required SNR for 1% packet error rate in spatially correlated channel for 256-QAM. We also show that LRA-BP requires much lower complexity compared with MRF-BP. 展开更多
关键词 MASSIVE MIMO MIMO DETECTION BELIEF propagation graph-based DETECTION LATTICE reduction MARKOV random field
3种虾肝肠胞虫PCR检测方法的应用比较分析 预览
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作者 叶键 许婷 +5 位作者 施礼科 陈凡 王力 陈喆 章秋虎 郭水荣 《水产科学》 CAS CSCD 北大核心 2019年第3期411-415,共5页
虾肝肠胞虫被认为是凡纳滨对虾“长不大”现象的主要病原之一,国内外学者已建立其PCR检测技术,包括18S-PCR、SSU-PCR及SWP-PCR。采集36个凡纳滨对虾苗种样本、5个卤虫样本和12个水样,应用上述3种PCR方法进行检测,并对阳性产物进行克隆... 虾肝肠胞虫被认为是凡纳滨对虾“长不大”现象的主要病原之一,国内外学者已建立其PCR检测技术,包括18S-PCR、SSU-PCR及SWP-PCR。采集36个凡纳滨对虾苗种样本、5个卤虫样本和12个水样,应用上述3种PCR方法进行检测,并对阳性产物进行克隆测序和序列同源性分析,以比较检测灵敏度和准确性。试验结果显示,18S-PCR在第一步扩增的灵敏度最好,SSU-PCR在第二步扩增的灵敏度显著高于SWP-PCR,但存在着一定的假阳性现象。建议在对凡纳滨对虾苗种进行虾肝肠胞虫的检测时,宜采用灵敏度更高的套式SSU-PCR方法。 展开更多
关键词 虾肝肠胞虫 检测 18S-PCR SSU-PCR SWP-PCR
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中国传统食醋微生物污染及控制措施研究进展 预览
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作者 王兴洁 刘爱平 +3 位作者 敖晓琳 吴远明 陈蓉 刘书亮 《食品与发酵工业》 CAS CSCD 北大核心 2019年第10期260-265,共6页
食醋微生物污染是导致食醋腐败变质的最主要原因,有效地检测和控制污染微生物是保证食醋安全以及进一步发展的基础。该文对食醋污染微生物的原因、危害以及种类进行了综述,开放式发酵环境及容器管道的不洁是食醋污染微生物的主要原因,... 食醋微生物污染是导致食醋腐败变质的最主要原因,有效地检测和控制污染微生物是保证食醋安全以及进一步发展的基础。该文对食醋污染微生物的原因、危害以及种类进行了综述,开放式发酵环境及容器管道的不洁是食醋污染微生物的主要原因,致使胀气、产膜、发黏及浑浊等现象发生,最终造成企业经济损失并对消费者健康造成隐患。总结了目前的检测方法和控制措施,现有的传统微生物培养检测方法弊端很多,非培养技术更能满足快速准确的检测要求。除加热和添加防腐剂等常用控制措施外,紫外线消毒、膜过滤等技术也逐渐应用。针对现有研究的不足,展望了食醋污染微生物未来的研究方向,以期为食醋污染微生物的深入研究及有效控制提供参考和理论依据。 展开更多
关键词 食醋加工 污染微生物 检测 控制
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空气负离子产生方法及其检测技术的研究进展
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作者 邢高娃 李宇 林金明 《分析试验室》 CAS CSCD 北大核心 2019年第1期112-118,共7页
空气负离子具有较高的反应活性,在环保、医疗等领域广泛应用。本文介绍空气负离子的产生方法,以及利用空气离子计数仪、离子迁移谱、质谱等几种检测空气负离子技术的研究进展,并展望了质谱检测方法的发展方向,以期为相关研究提供一定的... 空气负离子具有较高的反应活性,在环保、医疗等领域广泛应用。本文介绍空气负离子的产生方法,以及利用空气离子计数仪、离子迁移谱、质谱等几种检测空气负离子技术的研究进展,并展望了质谱检测方法的发展方向,以期为相关研究提供一定的参考。 展开更多
关键词 空气负离子 检测技术
免疫技术在动物源性食品快速检测中的研究进展 预览
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作者 职爱民 余曼 +1 位作者 乔苗苗 柴兴宽 《肉类研究》 北大核心 2019年第5期60-66,共7页
本文回顾了近年来免疫技术在动物源性食品快速检测中的应用研究,主要涵盖酶联免疫吸附测定法、胶体金免疫层析法、电化学免疫分析法、放射免疫法、荧光免疫分析法和免疫磁分离技术6种免疫技术对动物源性食品中抗生素、致病菌、激素、毒... 本文回顾了近年来免疫技术在动物源性食品快速检测中的应用研究,主要涵盖酶联免疫吸附测定法、胶体金免疫层析法、电化学免疫分析法、放射免疫法、荧光免疫分析法和免疫磁分离技术6种免疫技术对动物源性食品中抗生素、致病菌、激素、毒素、重金属、中枢神经系统组织和肉掺假检测的研究进展,以期为此领域的研究提供参考。 展开更多
关键词 免疫技术 动物源性食品 检测
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血清降钙素原与C-反应蛋白水平检测对患者早期感染的诊断 预览
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作者 周佳子 《中外医疗》 2019年第4期184-186,共3页
目的探讨血清降钙素原(PCT)、C-反应蛋白(CRP)检测在不同疾病早期感染中的诊断价值。方法回顾性分析2016年1月—2018年5月该院诊治的恶性肿瘤患者、艾滋病患者、早产儿共78例的血清实验室检查结果 :①比较三类疾病早期感染者、非感染者... 目的探讨血清降钙素原(PCT)、C-反应蛋白(CRP)检测在不同疾病早期感染中的诊断价值。方法回顾性分析2016年1月—2018年5月该院诊治的恶性肿瘤患者、艾滋病患者、早产儿共78例的血清实验室检查结果 :①比较三类疾病早期感染者、非感染者在血清PCT、CRP水平上的差异;②根据合并早期感染的42例患者是否为细菌感染,将其分为细菌感染组(n=26)、非细菌感染组(n=16),并比较两组血清PCT、CRP水平。结果①恶性肿瘤(PCT:t=7.658,P=0.000;CRP:t=16.165,P=0.000)、HIV感染(PCT:t=5.394,P=0.000;CRP:t=6.236,P=0.000)、早产儿的早期感染者(PCT:t=5.594,P=0.000;CRP:t=6.872,P=0.000)的血清PCT、CRP水平均高于非感染者(P<0.05);②细菌感染组患者的血清PCT、CRP水平均明显高于非细菌感染组(PCT:t=7.329,P=0.000;CRP:t=6.880,P=0.000)。结论在癌症、艾滋病和早产儿患者中,早期感染患者的血清PCT、CRP水平显著增高,且细菌感染、非细菌感染患者血清PCT、CRP水平差异也有统计学意义,表明血清降钙素原、C-反应蛋白检测水平在不同疾病早期感染的诊断中具有重要应用价值。 展开更多
关键词 血清降钙素原 C-反应蛋白 检测 早期感染 诊断价值
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食品塑料包装质量安全及检测探讨 预览
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作者 郄雯 《现代食品》 2019年第7期120-122,共3页
在日常生活中,食物的贩卖不仅仅单纯只有食物,越来越多的食物被套上了包装,以方便食物的运输、保存、贩卖及食用。塑料,作为一种轻薄、便宜又干净的物质,在食物的包装上得到广泛应用。但是食品的塑料包装是否安全,是否会严重影响到食物... 在日常生活中,食物的贩卖不仅仅单纯只有食物,越来越多的食物被套上了包装,以方便食物的运输、保存、贩卖及食用。塑料,作为一种轻薄、便宜又干净的物质,在食物的包装上得到广泛应用。但是食品的塑料包装是否安全,是否会严重影响到食物的安全性,是否会对对人体产生负面影响,这些问题引起了人们的重视。本文探讨分析了食品塑料包装质量安全及检测的方法,以做出合理的分析与建议。 展开更多
关键词 食品塑料包装 安全性 检测
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反射法槽波地震勘探技术在工作面探测中的应用 预览
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作者 李荣 《陕西煤炭》 2019年第2期97-100,共4页
断裂构造是矿井采掘中最常见的地质构造形态。准确判定断裂构造的发育形态,可以指导工作面的布置,有效回收呆滞资源,通过反射法槽波地震勘探,发现一条新的断层,对设计进行了修改,钻探验证了物探成果,给企业增加利润650万元。
关键词 槽波 断层 探测
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角膜内皮细胞相关基础及临床研究的现状 预览
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作者 苏冠羽 王乐滢 梁庆丰 《中华眼科医学杂志(电子版)》 2019年第2期118-123,共6页
角膜内皮细胞(HCECs)是保证角膜透明的重要结构,在角膜后弹力层和前房之间,具有屏障和离子泵功能,防止前房房水进入角膜的同时又可以将角膜基质中的水分转移至前房,维持角膜正常厚度。当HCECs损伤、密度下降到一定程度时,这种平衡被打破... 角膜内皮细胞(HCECs)是保证角膜透明的重要结构,在角膜后弹力层和前房之间,具有屏障和离子泵功能,防止前房房水进入角膜的同时又可以将角膜基质中的水分转移至前房,维持角膜正常厚度。当HCECs损伤、密度下降到一定程度时,这种平衡被打破,就会产生角膜水肿等角膜疾病。因此,HCECs在角膜组织解剖中的作用十分重要。此外,目前在体HCECs是不可再生的,一旦损害,视力将会严重受损。本文中笔者就HCECs的正常生理、损伤机制、检测、治疗及再生的研究情况进行综述。 展开更多
关键词 角膜内皮细胞 损伤机制 检测 治疗 再生
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Revision of CG Flash Density Based on Lightning Location Data 预览
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作者 Peng Guoping 《气象与环境研究:英文版》 CAS 2019年第2期69-72,77共5页
Using the data of the Lightning Location System( LLS) over Hubei Province,through the analysis of the distribution characteristics of CG( Cloud-to-Ground) flash density in 2015,it was found that the layout of the dete... Using the data of the Lightning Location System( LLS) over Hubei Province,through the analysis of the distribution characteristics of CG( Cloud-to-Ground) flash density in 2015,it was found that the layout of the detection station had influence on the spatial distribution of lightning.Grid CG flash density data were used to characterize the spatial distribution of the CG flash,and station distance factor was used to characterize the detection station layout. The result showed that there existed negative correlation between density and factor,significant correlation between the density component and the factor for the lightning current amplitude of 5 to 30 kA,and insignificant correlation between >30 kA of density component and factor. So it is necessary to revise the density to eliminate the influence of the station layout. On the basis of the linear regression method and its residual theory,the revision model of the grid CG flash density and the statistical model of relative detection efficiency were established. The result consistency of segment and non-segmented revision of the density was verified. Through the contrastive analysis of theoretical detection efficiency and relative detection efficiency,the feasibility for revision method of CG flash density and the statistical method of relative detection efficiency was also verified. 展开更多
关键词 LIGHTNING location system LATITUDE and LONGITUDE grid REVISION of CG flash DENSITY Detection efficiency Regression analysis RESIDUAL theory
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矿用带式输送机跑偏控制系统研究 预览
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作者 曹高生 李志强 蒋刚 《机械与电子》 2019年第3期59-61,共3页
针对带式输送机输送带的跑偏问题,为提高其工作稳定性,分析了输送带的跑偏原因和常用的跑偏控制措施,提出一种跑偏控制系统的总体结构和功能。在此基础上,分别提出了跑偏检测装置和纠偏装置的设计方案,并对跑偏控制系统的逻辑控制策略... 针对带式输送机输送带的跑偏问题,为提高其工作稳定性,分析了输送带的跑偏原因和常用的跑偏控制措施,提出一种跑偏控制系统的总体结构和功能。在此基础上,分别提出了跑偏检测装置和纠偏装置的设计方案,并对跑偏控制系统的逻辑控制策略进行了研究。 展开更多
关键词 带式输送机 跑偏 检测 纠偏
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循环外泌体检测在胰腺癌临床早期诊断的研究新进展
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作者 王媛媛 丁宇 +4 位作者 谭钺洸 毛娟 朱玲 丁克祥 戴萌 《国际老年医学杂志》 2019年第2期111-115,共5页
胰腺癌是一种高度致命的恶件肿瘤,缺乏早期临床诊断的高敏感和高特异的标记物胰腺癌患者外泌体町以由外周循环血中分离获得,含有大量信息物质,如磷脂酰肌醇聚糖-1 (GPC1)、外泌体衍生DNA的K-ras突变、微小RNA (miRNA)以及最新发现的循环... 胰腺癌是一种高度致命的恶件肿瘤,缺乏早期临床诊断的高敏感和高特异的标记物胰腺癌患者外泌体町以由外周循环血中分离获得,含有大量信息物质,如磷脂酰肌醇聚糖-1 (GPC1)、外泌体衍生DNA的K-ras突变、微小RNA (miRNA)以及最新发现的循环RNA ( circRNA)d等,可为早期发现和诊断胰腺癌提供依据。外泌体的检测目前只是一个辅助诊断或者互补检测指标,随着对外泌体分子生物学功能研究的深入,在临床上提高其对胰腺癌检测的特异性、敏感件、精确件和可重复性,外泌体有望成为胰腺癌临床早期诊断和精确诊断的重要标记分子。 展开更多
关键词 胰腺癌 外泌体 检测 早期诊断 研究进展
增压防堵真空预压法在吹填土加固工程的应用 预览
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作者 杨仲虎 姚永新 《浙江水利科技》 2019年第3期38-41,共4页
真空预压法是排水固结方法的一种,具有加固时间短、造价低、工艺简单等特点,适用于大面积吹填土软基处理。传统排水板真空预压普遍存在淤堵问题,影响加固效果。以温州市洞头县软基处理工程为例,采用增压防堵真空预压法,排水板得到有效... 真空预压法是排水固结方法的一种,具有加固时间短、造价低、工艺简单等特点,适用于大面积吹填土软基处理。传统排水板真空预压普遍存在淤堵问题,影响加固效果。以温州市洞头县软基处理工程为例,采用增压防堵真空预压法,排水板得到有效防堵。在规定工期内,吹填土加固检测结果达到设计要求。 展开更多
关键词 真空预压 吹填土 增压防堵 检测
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