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Effect of land use on soil nematode community composition and co-occurrence network relationship
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作者 Xiaotong Liu Siwei Liang +3 位作者 Yijia Tian Xiao Wang Wenju Liang Xiaoke Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2807-2819,共13页
Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and functions.To characterize the effect of land use on soil biota,soil nematode communities in crop land,for... Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and functions.To characterize the effect of land use on soil biota,soil nematode communities in crop land,forest land and fallow land were investigated in six regions of northern China.Generic richness,diversity,abundance and biomass of soil nematodes was the lowest in crop land.The richness and diversity of soil nematodes were 28.8and 15.1%higher in fallow land than in crop land,respectively.No significant differences in soil nematode indices were found between forest land and fallow land,but their network keystone genera composition was different.Among the keystone genera,50%of forest land genera were omnivores-predators and 36%of fallow land genera were bacterivores.The proportion of fungivores in forest land was 20.8%lower than in fallow land.The network complexity and the stability were lower in crop land than forest land and fallow land.Soil pH,NH_(4)^(+)-N and NO_(3)^(–)-N were the major factors influencing the soil nematode community in crop land while soil organic carbon and moisture were the major factors in forest land.Soil nematode communities in crop land influenced by artificial management practices were more dependent on the soil environment than communities in forest land and fallow land.Land use induced soil environment variation and altered network relationships by influencing trophic group proportions among keystone nematode genera. 展开更多
关键词 soil nematode trophic groups community composition co-occurrence network land use
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Machine learning prediction model for gray-level co-occurrence matrix features of synchronous liver metastasis in colorectal cancer
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作者 Kai-Feng Yang Sheng-Jie Li +1 位作者 Jun Xu Yong-Bin Zheng 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1571-1581,共11页
BACKGROUND Synchronous liver metastasis(SLM)is a significant contributor to morbidity in colorectal cancer(CRC).There are no effective predictive device integration algorithms to predict adverse SLM events during the ... BACKGROUND Synchronous liver metastasis(SLM)is a significant contributor to morbidity in colorectal cancer(CRC).There are no effective predictive device integration algorithms to predict adverse SLM events during the diagnosis of CRC.AIM To explore the risk factors for SLM in CRC and construct a visual prediction model based on gray-level co-occurrence matrix(GLCM)features collected from magnetic resonance imaging(MRI).METHODS Our study retrospectively enrolled 392 patients with CRC from Yichang Central People’s Hospital from January 2015 to May 2023.Patients were randomly divided into a training and validation group(3:7).The clinical parameters and GLCM features extracted from MRI were included as candidate variables.The prediction model was constructed using a generalized linear regression model,random forest model(RFM),and artificial neural network model.Receiver operating characteristic curves and decision curves were used to evaluate the prediction model.RESULTS Among the 392 patients,48 had SLM(12.24%).We obtained fourteen GLCM imaging data for variable screening of SLM prediction models.Inverse difference,mean sum,sum entropy,sum variance,sum of squares,energy,and difference variance were listed as candidate variables,and the prediction efficiency(area under the curve)of the subsequent RFM in the training set and internal validation set was 0.917[95%confidence interval(95%CI):0.866-0.968]and 0.09(95%CI:0.858-0.960),respectively.CONCLUSION A predictive model combining GLCM image features with machine learning can predict SLM in CRC.This model can assist clinicians in making timely and personalized clinical decisions. 展开更多
关键词 Colorectal cancer Synchronous liver metastasis Gray-level co-occurrence matrix Machine learning algorithm Prediction model
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The Citron homology domain of MAP4Ks improves outcomes of traumatic brain injury
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作者 Xiaoling Zhong Wenjiao Tai +4 位作者 Meng-Lu Liu Shuaipeng Ma Tianjin Shen Yuhua Zou Chun-Li Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3233-3244,共12页
The mitogen-activated protein kinase kinase kinase kinases(MAP4Ks)signaling pathway plays a pivotal role in axonal regrowth and neuronal degeneration following insults.Whether targeting this pathway is beneficial to b... The mitogen-activated protein kinase kinase kinase kinases(MAP4Ks)signaling pathway plays a pivotal role in axonal regrowth and neuronal degeneration following insults.Whether targeting this pathway is beneficial to brain injury remains unclear.In this study,we showed that adeno-associated virus-delivery of the Citron homology domain of MAP4Ks effectively reduces traumatic brain injury-induced reactive gliosis,tauopathy,lesion size,and behavioral deficits.Pharmacological inhibition of MAP4Ks replicated the ameliorative effects observed with expression of the Citron homology domain.Mechanistically,the Citron homology domain acted as a dominant-negative mutant,impeding MAP4K-mediated phosphorylation of the dishevelled proteins and thereby controlling the Wnt/β-catenin pathway.These findings implicate a therapeutic potential of targeting MAP4Ks to alleviate the detrimental effects of traumatic brain injury. 展开更多
关键词 adeno-associated virus Citron homology Citron homology domain gene therapy mitogen-activated protein kinase kinase kinase kinases traumatic brain injury
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Interaction of major facilitator superfamily domain containing 2A with the blood-brain barrier
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作者 Yilun Ma Taiwei Dong +3 位作者 Fei Luan Juanjuan Yang Feng Miao Peifeng Wei 《Neural Regeneration Research》 SCIE CAS 2025年第8期2133-2152,共20页
The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the bloo... The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly understood.The major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier function.It plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier,in addition to the transport of lipids,such as docosahexaenoic acid,across the blood-brain barrier.Furthermore,an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases;however,little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain barrier.This paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier,including their basic structures and functions,cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier,and the in-depth studies on lipid transport and the regulation of blood-brain barrier permeability.This comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to date.This will not only help to elucidate the pathogenesis of neurological diseases,improve the accuracy of laboratory diagnosis,and optimize clinical treatment strategies,but it may also play an important role in prognostic monitoring.In addition,the effects of major facilitator superfamily domain containing 2A on blood-brain barrier leakage in various diseases and the research progress on cross-blood-brain barrier drug delivery are summarized.This review may contribute to the development of new approaches for the treatment of neurological diseases. 展开更多
关键词 blood-brain barrier(BBB) caveolin-1 central nervous system docosahexaenoic acid endothelial cells LYSOPHOSPHATIDYLCHOLINE major facilitator superfamily domain containing 2A(MFSD2A) TRANSCYTOSIS
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基于co-occurrence相似度的聚类集成方法 被引量:3
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作者 凌光 王明春 冯嘉毅 《计算机应用》 CSCD 北大核心 2011年第2期441-445,461,共6页
首先提出了一种基于属性值的co-occurrence相似度概念,通过对其进一步的研究,提出了3个等价性表述;然后对属性值之间的co-occurrence相似度进行引申,给出了数据对象之间co-occurrence相似度的定义,并将其成功应用到聚类集成方法中。利用... 首先提出了一种基于属性值的co-occurrence相似度概念,通过对其进一步的研究,提出了3个等价性表述;然后对属性值之间的co-occurrence相似度进行引申,给出了数据对象之间co-occurrence相似度的定义,并将其成功应用到聚类集成方法中。利用co-occurrence相似度在计算某个初始聚类结果中数据对象之间的相似度时,充分考虑了其他初始聚类结果和该初始聚类结果之间的相互影响和联系。实验表明,基于co-occurrence相似度的聚类集成(CSCE)方法能有效识别数据之间的细微结构,有助于提高聚类集成的效果。 展开更多
关键词 聚类集成 binary相似度 co-occurrence相似度 基于簇相似的划分算法 基于co-occurrence相似度的聚类集成
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基于加权co-occurrence矩阵的聚类集成算法
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作者 柏建普 杨亚坤 《电子科技》 2012年第2期19-22,共4页
聚类集成是数据挖掘研究的一个热点。它是利用同一数据集的多个聚类划分集成在一起,以提高聚类分析的性能。当前相关研究大多没有考虑进行集成的聚类成员的质量,因此较差的成员会对集成结果产生不良影响。文中提出了一种基于加权co-occu... 聚类集成是数据挖掘研究的一个热点。它是利用同一数据集的多个聚类划分集成在一起,以提高聚类分析的性能。当前相关研究大多没有考虑进行集成的聚类成员的质量,因此较差的成员会对集成结果产生不良影响。文中提出了一种基于加权co-occurrence矩阵的聚类集成算法(WCSCE)。该方法首先计算出聚类成员基于属性值的co-occurrence矩阵,然后对聚类成员的质量进行简单评价并赋予权重,生成加权co-occurrence矩阵,进而产生集成结果。最后通过实验验证了该算法的有效性,并提高了聚类质量。 展开更多
关键词 聚类集成 co-occurrence矩阵 权重
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Co-occurrence Patterns of Above-ground and Below-ground Mite Communities in Farmland of Sanjiang Plain, Northeast China 被引量:7
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作者 LIN Lin GAO Meixiang +3 位作者 LIU Dong ZHANG Xueping WU Haitao WU Donghui 《Chinese Geographical Science》 SCIE CSCD 2014年第3期339-347,共9页
One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, litt... One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The pattern of the above-ground mite commu- nity was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite com- munities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale. 展开更多
关键词 above-ground mite below-ground mite mite communities co-occurrence patterns interspecific competition species pairassociations
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Artificial intelligence on diabetic retinopathy diagnosis: an automatic classification method based on grey level co-occurrence matrix and naive Bayesian model 被引量:6
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作者 Kai Cao Jie Xu Wei-Qi Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第7期1158-1162,共5页
AIM: To develop an automatic tool on screening diabetic retinopathy(DR) from diabetic patients.METHODS: We extracted textures from eye fundus images of each diabetes subject using grey level co-occurrence matrix metho... AIM: To develop an automatic tool on screening diabetic retinopathy(DR) from diabetic patients.METHODS: We extracted textures from eye fundus images of each diabetes subject using grey level co-occurrence matrix method and trained a Bayesian model based on these textures. The receiver operating characteristic(ROC) curve was used to estimate the sensitivity and specificity of the Bayesian model.RESULTS: A total of 1000 eyes fundus images from diabetic patients in which 298 eyes were diagnosed as DR by two ophthalmologists. The Bayesian model was trained using four extracted textures including contrast, entropy, angular second moment and correlation using a training dataset. The Bayesian model achieved a sensitivity of 0.949 and a specificity of 0.928 in the validation dataset. The area under the ROC curve was 0.938, and the 10-fold cross validation method showed that the average accuracy rate is 93.5%.CONCLUSION: Textures extracted by grey level cooccurrence can be useful information for DR diagnosis, and a trained Bayesian model based on these textures can be an effective tool for DR screening among diabetic patients. 展开更多
关键词 GREY level co-occurrence matrix Bayesian textures artificial INTELLIGENCE receiver operating characteristiccurve DIABETIC RETINOPATHY
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Combined effects of habitat and interspec ificinteraction define co-occurrence patterns of sympatric Galliformes 被引量:5
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作者 Lijun Chen Zufei Shu +3 位作者 Wutao Yao Yong Ma Wenhong Xiao Xiaoqun Huang 《Avian Research》 CSCD 2019年第3期344-356,共13页
Background:Disentangling the relative importance of environmental variables and interspecific interaction in modulating co-occurrence patterns of sympatric species is essential for understanding the mechanisms of comm... Background:Disentangling the relative importance of environmental variables and interspecific interaction in modulating co-occurrence patterns of sympatric species is essential for understanding the mechanisms of community assembly and biodiversity. For the two sympatric Galliformes, Silver Pheasants (Lophura nycthemera) and Whitenecklaced Partridges (Arborophila gingica), we know little about the role of habitat use and interspecific interactions in modulating their coexistence. Methods:We adopted a probabilistic approach incorporating habitat preference and interspecific interaction using occupancy model to account for imperfect detection,and used daily activity pattern analysis to investigate the cooccurrence pattern of these two sympatric Galliformes in wet and dry seasons. Results: We found that the detection probability of Silver Pheasant and White-necklaced Partridge were related to habitat variables and interspecific interaction. The presence of Silver Pheasant increases the detection probability of White-necklaced Partridge in both the wet and dry season. However, the presence of White-necklaced Partridges increases the detection probability of Silver Pheasants in the wet season, but decreases the probability in the dry season. Further, Silver Pheasants were detected frequently in the sites of high values of enhanced vegetable index (EVI) in both the wet and dry season, and in sites away from human residential settlement in the wet season. Whitenecklaced partridges were mainly detected in low EVI sites. The site use probabilities of two Galliformes were best explained by habitat variables, Silver Pheasants and White-necklaced Partridges preferred steeper areas during the wet and dry season. Both species mainly occurred in low EVI areas during the wet season and occupied sites away from the resident settlement during the dry season. Moreover, the site use probabilities of two species had opposite relationships with forest canopy coverage. Silver Pheasants preferred areas with high forest canopy coverage whereas White-necklaced Partridges preferred low forest canopy coverage in the dry season, and vice versa in the wet season. Species interaction factor (SIF)corroborated weak evidence of the dependence of the site use of one species on that of the other in the either dry or wet season.Temporally, high overlapping of daily activity pattern indicated no significantly temporal niche differentiation between sympatric Galliformes in both wet and dry seasons. Conclusions:Our results demonstrated that the presence of two species influenced the detection probability interactively and there was no temporal partitioning in activity time between Silver Pheasants and White-necklaced Partridges in the wet and dry seasons.The site use probability of two Galliformes was best explained by habitat variables, especially the forest canopy coverage.Therefore, environmental variables and interspecific interaction are the leading drivers regulating the detection and site use probability and promoting co-occurrence of Silver Pheasants and White-necklaced Partridges. 展开更多
关键词 Arborophila gingica co-occurrence HABITAT preference INTERSPECIFIC interaction Lophura nycthemera OCCUPANCY model
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Inversion tillage with straw incorporation affects the patterns of soil microbial co-occurrence and multi-nutrient cycling in a Hapli-Udic Cambisol 被引量:2
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作者 CHEN Xu HAN Xiao-zeng +4 位作者 WANG Xiao-hui GUO Zhen-xi YAN Jun LU Xin-chun ZOU Wen-xiu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1546-1559,共14页
Inversion tillage with straw amendment is widely applied in northeastern China, and it can substantially increase the storage of carbon and improve multiple subsoil functions. Soil microorganisms are believed to be th... Inversion tillage with straw amendment is widely applied in northeastern China, and it can substantially increase the storage of carbon and improve multiple subsoil functions. Soil microorganisms are believed to be the key to this process,but research into their role in subsoil amelioration is limited. Therefore, a field experiment was conducted in 2018 in a region in northeastern China with Hapli-Udic Cambisol using four treatments: conventional tillage(CT, tillage to a depth of 15 cm with no straw incorporation), straw incorporation with conventional tillage(SCT, tillage to a depth of 15 cm),inversion tillage(IT, tillage to a depth of 35 cm) and straw incorporation with inversion tillage(SIT, tillage to a depth of 35 cm). The soils were managed by inversion to a depth of 15 or 35 cm every year after harvest. The results indicated that SIT improved soil multi-nutrient cycling variables and increased the availability of key nutrients such as soil organic carbon, total nitrogen, available nitrogen, available phosphorus and available potassium in both the topsoil and subsoil.In contrast to CT and SCT, SIT created a looser microbial network structure but with highly centralized clusters by reducing the topological properties of average connectivity and node number, and by increasing the average path length and the modularity. A Random Forest analysis found that the average path length and the clustering coefficient were the main determinants of soil multi-nutrient cycling. These findings suggested that SIT can be an effective option for improving soil multi-nutrient cycling and the structure of microbial networks, and they provide crucial information about the microbial strategies that drive the decomposition of straw in Hapli-Udic Cambisol. 展开更多
关键词 SOIL microbiome microbial co-occurrence networks STRAW amendment SOIL nutrient
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Assembly and co-occurrence patterns of rare and abundant bacterial sub-communities in rice rhizosphere soil under short-term nitrogen deep placement 被引量:2
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作者 LI Gui-long WU Meng +5 位作者 LI Peng-fa WEI Shi-ping LIU Jia JIANG Chun-yu LIU Ming LI Zhong-pei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第12期3299-3311,共13页
Nitrogen(N)deep placement has been found to reduce N leaching and increase N use efficiency in paddy fields.However,relatively little is known how bacterial consortia,especially abundant and rare taxa,respond to N dee... Nitrogen(N)deep placement has been found to reduce N leaching and increase N use efficiency in paddy fields.However,relatively little is known how bacterial consortia,especially abundant and rare taxa,respond to N deep placement,which is critical for understanding the biodiversity and function of agricultural ecosystem.In this study,lllumina sequencing and ecological models were conducted to examine the diversity patterns and underlying assembly mechanisms of abundant and rare taxa in rice rhizosphere soil under different N fertilization regimes at four rice growth stages in paddy fields.The results showed that abundant and rare bacteria had distinct distribution patterns in rhizosphere samples.Abundant bacteria showed ubiquitous distribution;while rare taxa exhibited uneven distribution across all samples.Stochastic processes dominated community assembly of both abundant and rare bacteria,with dispersal limitation playing a more vital role in abundant bacteria,and undominated processes playing a more important role in rare bacteria.The N deep placement was associated with a greater influence of dispersal limitation than the broadcast N fertilizer(BN)and no N fertilizer(NN)treatments in abundant and rare taxa of rhizosphere soil;while greater contributions from homogenizing dispersal were observed for BN and NN in rare taxa.Network analysis indicated that abundant taxa with closer relationships were usually more likely to occupy the central position of the network than rare taxa.Nevertheless,most of the keystone species were rare taxa and might have played essential roles in maintaining the network stability.Overall,these findings highlighted that the ecological mechanisms and co-occurrence patterns of abundant and rare bacteria in rhizosphere soil under N deep placement. 展开更多
关键词 rare bacteria community assembly network analysis co-occurrence patterns N deep placement
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Co-occurrence of IPMN and malignant IPNB complicated by a pancreatobiliary fistula: A case report and review of the literature 被引量:6
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作者 Xu Ren Chun-Lan Zhu +3 位作者 Xu-Fu Qin Hong Jiang Tian Xia Yong-Ping Qu 《World Journal of Clinical Cases》 SCIE 2019年第1期102-108,共7页
BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB) is pathologically similar to intraductal papillary mucinous neoplasm(IPMN). However, there are several significant differences between them. The rate of... BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB) is pathologically similar to intraductal papillary mucinous neoplasm(IPMN). However, there are several significant differences between them. The rate of IPMN associated with extrapancreatic malignancies has been reported to range from 10%-40%, and it may occasionally be complicated with the presence of fistulas. IPMN associated with malignant IPNB is extremely rare and only nine cases have been reported in the literature.CASE SUMMARY We report a 52-year-old man who presented with recurrent cholangitis for nine months. Computed tomography and magnetic resonance cholangiopancreatography showed the common bile duct stricture with dilated pancreatobiliary duct without other abnormal findings. The underlying pathogenesis could not be identified based on the radiologic images. Endoscopic retrograde cholangiopancreatography revealed a pancreatobiliary fistula with dilated main pancreatic duct, biliary stricture with dilated biliary tree, and mucus discharge from the enlarged orifice of the major papilla. The patient underwent SpyGlass cholangiopancreatoscopy due to a suspected mucin-producing biliary neoplasm and indeterminate main pancreatic duct dilatation. Multiple papillary growing neoplasms with vascular images, with the extent of lesions spreading in the biliopancreatic ductal lumens, were identified by SpyGlass. In addition, the presence of a pancreatobiliary fistula was also identified. The patient was diagnosed as having benign IPMN and malignant IPNB with focal invasion by postoperative pathology. Furthermore, varying histological subtypes were present in both IPMN and IPNB. Pylorus-preserving pancreaticoduodenectomy was performed on the patient with excellent results during the 52 month followup period.CONCLUSION We deemed that pancreatography and SpyGlass allowed for an efficient diagnosis of IPMN with pancreatobiliary fistula, whereas the etiology could not be identified by radiologic imaging. 展开更多
关键词 INTRADUCTAL PAPILLARY MUCINOUS NEOPLASM of the pancreas INTRADUCTAL PAPILLARY NEOPLASM of the bile duct Extrapancreatic malignancies co-occurrence Pancreatobiliary fistula SpyGlass cholangiopancreatoscopy Endoscopic retrograde cholangiopancreatography Case report
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Binary Image Steganalysis Based on Distortion Level Co-Occurrence Matrix 被引量:2
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作者 Junjia Chen Wei Lu +4 位作者 Yuileong Yeung Yingjie Xue Xianjin Liu Cong Lin Yue Zhang 《Computers, Materials & Continua》 SCIE EI 2018年第5期201-211,共11页
In recent years,binary image steganography has developed so rapidly that the research of binary image steganalysis becomes more important for information security.In most state-of-the-art binary image steganographic s... In recent years,binary image steganography has developed so rapidly that the research of binary image steganalysis becomes more important for information security.In most state-of-the-art binary image steganographic schemes,they always find out the flippable pixels to minimize the embedding distortions.For this reason,the stego images generated by the previous schemes maintain visual quality and it is hard for steganalyzer to capture the embedding trace in spacial domain.However,the distortion maps can be calculated for cover and stego images and the difference between them is significant.In this paper,a novel binary image steganalytic scheme is proposed,which is based on distortion level co-occurrence matrix.The proposed scheme first generates the corresponding distortion maps for cover and stego images.Then the co-occurrence matrix is constructed on the distortion level maps to represent the features of cover and stego images.Finally,support vector machine,based on the gaussian kernel,is used to classify the features.Compared with the prior steganalytic methods,experimental results demonstrate that the proposed scheme can effectively detect stego images. 展开更多
关键词 Binary image steganalysis informational security embedding distortion distortion level map co-occurrence matrix support vector machine.
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An Efficient Algorithm for Discovering Co-occurrence Concepts Through Pathfinder Paradigm 被引量:1
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作者 杜志典 WANG James 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期153-156,160,共5页
The Pathfinder paradigm has been used in generating and analyzing graph models that support clustering similar concepts and minimum-cost paths to provide an associative network structure within a domain. The co-occurr... The Pathfinder paradigm has been used in generating and analyzing graph models that support clustering similar concepts and minimum-cost paths to provide an associative network structure within a domain. The co-occurrence pathfinder network ( CPFN ) extends the traditional pathfinder paradigm so that co-occurring concepts can be calculated at each sampling time. Existing algorithms take O(n(s)) time to calculate the pathfinder network (PFN) at each sampling time for a non-completed input graph of a CPFN (r = ∞, q = n - 1), where n is the number of nodes in the input graph, r is the Minkowski exponent and q is the maximum number of links considered in finding a minimum cost path between vertices. To reduce the complexity of calculating the CPFN, we propose a greedy based algorithm, MEC(G) algorithm, which takes shortcuts to avoid unnecessary steps in the existing algorithms, to correctly calculate a CPFN (r = ∞, q= n - 1) in O(klogk) time where k is the number of edges of the input graph. Our example demonstrates the efficiency and correctness of the proposed MEC(G) algorithm, confirming our mathematic analysis on this algorithm. 展开更多
关键词 PATHFINDER CPFN co-occurrence.
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Outlining the keyword co-occurrence trends in Shuanghuanglian injection research: A bibliometric study using CiteSpace Ⅲ 被引量:3
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作者 Qin Zhang Guang Rong +3 位作者 Qinggang Meng Mang Yu Qingyu Xie Jian Fang 《Journal of Traditional Chinese Medical Sciences》 2020年第2期189-198,共10页
Objective:To explore the evolvement and new trends in the use of Shuanghuanglian injection(SHLI).Methods:China National Knowledge Infrastructure(CNKI),PubMed,and Embase were extensively searched using the search terms... Objective:To explore the evolvement and new trends in the use of Shuanghuanglian injection(SHLI).Methods:China National Knowledge Infrastructure(CNKI),PubMed,and Embase were extensively searched using the search terms“Shuanghuanglian injection”and“Shuanghuanglian fenzhen”to retrieve articles relevant to SHLI(1992e2020).Retrieved articles were further investigated by two authors to exclude those unrelated to SHLI.The bibliographical references of the included articles were exported as raw data and then treated using the CiteSpace tool to visualize the mapping of the SHLI research domain.Essential clusters and highly frequent keywords were quantified for further analysis.The clusters were automatically labeled by the algorithm of tf*idf for objective analysis.Basic bibliometric features,including article types and yearly trend in article numbers were also determined and discussed.Results:The modules of the keywords of interest presented clear boundaries with a high modularity score(Q=0.73).High-confidence clusters were identified,including bioactivity fingerprint(S=0.99),equal pupils(S=0.91),drug preparation department(S=0.87),difficulty in respiration(S=0.85),peristalsis(0.88),and Danshen powder injection(S=0.94).The characteristic keywords in terms of frequency and burstiness were Shuanghuanglian powder for injection(F=235,B=5.22),SHLI(F=112,B=11.39),and adverse drug reactions(ADRs;F=104,B=7.35).Conclusion:In the field of SHLI study,there are five major topic categories:bioactivity fingerprint;ADR mechanism and cause detection;proper preparation;clinical evidence accumulation;and efficacy in diseases with no effective treatment and combination usage.The trend for using modern methodologies from a science-based perspective to study SHLI will continue to exist.The causes of multi-factorial ADRs may be an important topic for future studies. 展开更多
关键词 Shuanghuanglian injection Bibliometric study domain knowledge CITESPACE
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Seasonal co-occurrence patterns of bacteria and eukaryotic phytoplankton and the ecological response in urban aquatic ecosystem 被引量:1
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作者 Jing YANG Xiongjie ZHANG +5 位作者 Junping LÜ Qi LIU Fangru NAN Xudong LIU Shulian XIE Jia FENG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第4期1508-1529,共22页
Microorganisms play a key role in aquatic ecosystems.Recent studies show that keystone taxa in microbial community could change the community structure and function.However,most previous studies focus on abundant taxa... Microorganisms play a key role in aquatic ecosystems.Recent studies show that keystone taxa in microbial community could change the community structure and function.However,most previous studies focus on abundant taxa but neglected low abundant ones.To clarify the seasonal variation of bacterial and microalgal communities and understand their synergistic adaptation to diff erent environmental factors,we studied the bacterial and eukaryotic phytoplankton communities in Fenhe River that runs through Taiyuan City,central China,and their seasonal co-occurrence patterns using 16S and 18S rDNA sequencing.Results indicate that positive interaction of eukaryotic phytoplankton network was more active than negative one except winter,indicating that the cooperation(symbiotic phenomenon in which phytoplankton are interdependent and mutually benefi cial)among them could improve the adaption of microbial community to the local environmental changes and maintain the stability of microbial network.The main genera that identifi ed as keystone taxa in bacterial network were Salinivibrio and Sphingopyxis of Proteobacteria and they could respond to the variation of nitrite and make use of it,while those that identifi ed as keystone taxa in eukaryotic phytoplankton network were Pseudoschroederia and Nannochloris,and they were more susceptible to nitrate and phosphate.Mychonastes and Cryptomonas were closely related to water temperature.However,the loss of the co-occurrence by environmental factor changes aff ected the stability of network structure.This study provided a reference for analyzing relationship between bacteria and eukaryotic phytoplankton and revealing potential importance of keystone taxa in similar ecological domains in carbon,nitrogen,and phosphorus dynamics. 展开更多
关键词 seasonal co-occurrence bacteria and eukaryotic phytoplankton communities keystone taxa ecological effect urban aquatic ecosystem
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A Metric Approach to Hot Topics in Biomedicine via Keyword Co-occurrence 被引量:1
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作者 Jane H.Qin Jean J.Wang Fred Y.Ye 《Journal of Data and Information Science》 CSCD 2019年第4期13-25,共13页
Purpose:To reveal the research hotpots and relationship among three research hot topics in b iomedicine,namely CRISPR,iPS(induced Pluripotent Stem)cell and Synthetic biology.Design/methodology/approach:We set up their... Purpose:To reveal the research hotpots and relationship among three research hot topics in b iomedicine,namely CRISPR,iPS(induced Pluripotent Stem)cell and Synthetic biology.Design/methodology/approach:We set up their keyword co-occurrence networks with using three indicators and information visualization for metric analysis.Findings:The results reveal the main research hotspots in the three topics are different,but the overlapping keywords in the three topics indicate that they are mutually integrated and interacted each other.Research limitations:All analyses use keywords,without any other forms.Practical implications:We try to find the information distribution and structure of these three hot topics for revealing their research status and interactions,and for promoting biomedical developments.Originality/value:We chose the core keywords in three research hot topics in biomedicine by using h-index. 展开更多
关键词 Keyword co-occurrence Network analysis Information visualization BIOMEDICINE Hot topics CRISPR-Cas iPS cell Synthetic biology
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Material microstructures analyzed by using gray level Co-occurrence matrices 被引量:1
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作者 胡延苏 王志军 +2 位作者 樊晓光 李俊杰 高昂 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期483-490,共8页
The mechanical properties of materials greatly depend on the microstructure morphology. The quantitative characterization of material microstructures is essential for the performance prediction and hence the material ... The mechanical properties of materials greatly depend on the microstructure morphology. The quantitative characterization of material microstructures is essential for the performance prediction and hence the material design. At present,the quantitative characterization methods mainly rely on the microstructure characterization of shape, size, distribution,and volume fraction, which related to the mechanical properties. These traditional methods have been applied for several decades and the subjectivity of human factors induces unavoidable errors. In this paper, we try to bypass the traditional operations and identify the relationship between the microstructures and the material properties by the texture of image itself directly. The statistical approach is based on gray level Co-occurrence matrix(GLCM), allowing an objective and repeatable study on material microstructures. We first present how to identify GLCM with the optimal parameters, and then apply the method on three systems with different microstructures. The results show that GLCM can reveal the interface information and microstructures complexity with less human impact. Naturally, there is a good correlation between GLCM and the mechanical properties. 展开更多
关键词 microstructures quantitative characterization mechanical properties gray level co-occurrence matrix
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3D Gray Level Co-Occurrence Matrix Based Classification of Favor Benign and Borderline Types in Follicular Neoplasm Images 被引量:1
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作者 Oranit Boonsiri Kiyotada Washiya +1 位作者 Kota Aoki Hiroshi Nagahashi 《Journal of Biosciences and Medicines》 2016年第3期51-56,共6页
Since the efficiency of treatment of thyroid disorder depends on the risk of malignancy, indeterminate follicular neoplasm (FN) images should be classified. The diagnosis process has been done by visual interpretation... Since the efficiency of treatment of thyroid disorder depends on the risk of malignancy, indeterminate follicular neoplasm (FN) images should be classified. The diagnosis process has been done by visual interpretation of experienced pathologists. However, it is difficult to separate the favor benign from borderline types. Thus, this paper presents a classification approach based on 3D nuclei model to classify favor benign and borderline types of follicular thyroid adenoma (FTA) in cytological specimens. The proposed method utilized 3D gray level co-occurrence matrix (GLCM) and random forest classifier. It was applied to 22 data sets of FN images. Furthermore, the use of 3D GLCM was compared with 2D GLCM to evaluate the classification results. From experimental results, the proposed system achieved 95.45% of the classification. The use of 3D GLCM was better than 2D GLCM according to the accuracy of classification. Consequently, the proposed method probably helps a pathologist as a prescreening tool. 展开更多
关键词 Thyroid Follicular Lesion 3D Gray Level co-occurrence Matrix Random Ferest Classifier
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The reflection of hierarchical cluster analysis of co-occurrence matrices in SPSS 被引量:5
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作者 Qiuju ZHOU Fuhai LENG Loet LEYDESDORFF 《Chinese Journal of Library and Information Science》 2015年第2期11-24,共14页
Purpose: To discuss the problems arising from hierarchical cluster analysis of co-occurrence matrices in SPSS, and the corresponding solutions. Design/methodology/approach: We design different methods of using the S... Purpose: To discuss the problems arising from hierarchical cluster analysis of co-occurrence matrices in SPSS, and the corresponding solutions. Design/methodology/approach: We design different methods of using the SPSS hierarchical clustering module for co-occurrence matrices in order to compare these methods. We offer the correct syntax to deactivate the similarity algorithm for clustering analysis within the hierarchical clustering module of SPSS. Findings: When one inputs co-occurrence matrices into the data editor of the SPSS hierarchical clustering module without deactivating the embedded similarity algorithm, the program calculates similarity twice, and thus distorts and overestimates the degree of similarity. Practical implications: We offer the correct syntax to block the similarity algorithm for clustering analysis in the SPSS hierarchical clustering module in the case of co-occurrence matrices. This syntax enables researchers to avoid obtaining incorrect results. Originality/value: This paper presents a method of editing syntax to prevent the default use of a similarity algorithm for SPSS's hierarchical clustering module. This will help researchers, especially those from China, to properly implement the co-occurrence matrix when using SPSS for hierarchical cluster analysis, in order to provide more scientific and rational results. 展开更多
关键词 co-occurrence matrices Hierarchical cluster analysis SPSS Similarity algorithm The syntax editor
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