Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and mai...Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed bridges.However,the representative temperatures of stayed cables are not specified in the existing design codes.To address this issue,this study investigates the distribution of the cable temperature and determinates its representative temperature.First,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature data.According to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature gradient.Then,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service life.These methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the cables.However,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their application.The proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges.展开更多
In order to carry out an integrated assessment of sea water quality objectively, this paper based on the concept and principle of artificial neural network, generated appropriate training samples for BP artificial neu...In order to carry out an integrated assessment of sea water quality objectively, this paper based on the concept and principle of artificial neural network, generated appropriate training samples for BP artificial neural network model through the method of producing samples to the concentration of various pollution index of sea water quality from the viewpoint of threshold, established the BP artificial neural network model of sea water quality assessment using multi-layer neural network with error back-propagation algorithm. This model was used to assess water environment and obtain sea water quality categories of offshore area in Bohai Bay through calculating. The calculations shown that pollution index in river's wet season was higher than that in dry season from 2004 to 2007, and the pollution was particularly serious in 2005 and 2006, but a little better in 2007. The assessed results of cases shown that the model was reasonable in design and higher in generalization, meanwhile, it was common, objective and practical to sea water quality assessment.展开更多
A vision-based color analysis system was developed for rapid estimation of copper content in the secondary copper smelting process. Firstly, cross section images of secondary copper samples were captured by the design...A vision-based color analysis system was developed for rapid estimation of copper content in the secondary copper smelting process. Firstly, cross section images of secondary copper samples were captured by the designed vision system. After the preprocessing and segmenting procedures, the images were selected according to their grayscale standard deviations of pixels and percentages of edge pixels in the luminance component. The selected images were then used to extract the information of the improved color vector angles, from which the copper content estimation model was developed based on the least squares support vector regression (LSSVR) method. For comparison, three additional LSSVR models, namely, only with sample selection, only with improved color vector angle, without sample selection or improved color vector angle, were developed. In addition, two exponential models, namely, with sample selection, without sample selection, were developed. Experimental results indicate that the proposed method is more effective for improving the copper content estimation accuracy, particularly when the sample size is small.展开更多
A cascaded projection of the Gaussian mixture model algorithm is proposed.First,the marginal distribution of the Gaussian mixture model is computed for different feature dimensions, and a number of sub-classifiers are...A cascaded projection of the Gaussian mixture model algorithm is proposed.First,the marginal distribution of the Gaussian mixture model is computed for different feature dimensions, and a number of sub-classifiers are generated using the marginal distribution model.Each sub-classifier is based on different feature sets.The cascaded structure is adopted to fuse the sub-classifiers dynamically to achieve sample adaptation ability.Secondly,the effectiveness of the proposed algorithm is verified on electrocardiogram emotional signal and speech emotional signal.Emotional data including fidgetiness,happiness and sadness is collected by induction experiments.Finally,the emotion feature extraction method is discussed,including heart rate variability, the chaotic electrocardiogram feature and utterance level static feature.The emotional feature reduction methods are studied, including principle component analysis,sequential forward selection, the Fisher discriminant ratio and maximal information coefficient.The experimental results show that the proposed classification algorithm can effectively improve recognition accuracy in two different scenarios.展开更多
Bagging is not quite suitable for stable classifiers such as nearest neighbor classifiers due to the lack of diversity and it is difficult to be directly applied to face recognition as well due to the small sample si...Bagging is not quite suitable for stable classifiers such as nearest neighbor classifiers due to the lack of diversity and it is difficult to be directly applied to face recognition as well due to the small sample size (SSS) property of face recognition. To solve the two problems,local Bagging (L-Bagging) is proposed to simultaneously make Bagging apply to both nearest neighbor classifiers and face recognition. The major difference between L-Bagging and Bagging is that L-Bagging performs the bootstrap sampling on each local region partitioned from the original face image rather than the whole face image. Since the dimensionality of local region is usually far less than the number of samples and the component classifiers are constructed just in different local regions,L-Bagging deals with SSS problem and generates more diverse component classifiers. Experimental results on four standard face image databases (AR,Yale,ORL and Yale B) indicate that the proposed L-Bagging method is effective and robust to illumination,occlusion and slight pose variation.展开更多
To study the capacity of artificial neural network (ANN) applying to battlefield target classification and result of classification, according to the characteristics of battlefield target acoustic and seismic sign...To study the capacity of artificial neural network (ANN) applying to battlefield target classification and result of classification, according to the characteristics of battlefield target acoustic and seismic signals, an on the spot experiment was carried out to derive acoustic and seismic signals of a tank and jeep by special experiment system. Experiment data processed by fast Fourier transform(FFT) were used to train the ANN to distinguish the two battlefield targets. The ANN classifier was performed by the special program based on the modified back propagation (BP) algorithm. The ANN classifier has high correct identification rates for acoustic and seismic signals of battlefield targets, and is suitable for the classification of battlefield targets. The modified BP algorithm eliminates oscillations and local minimum of the standard BP algorithm, and enhances the convergence rate of the ANN.展开更多
Support vector machines (SVMs) are combined with the artificial immune network (aiNet), thus forming a new hybrid ai-SVM algorithm. The algorithm is used to reduce the number of samples and the training time of SV...Support vector machines (SVMs) are combined with the artificial immune network (aiNet), thus forming a new hybrid ai-SVM algorithm. The algorithm is used to reduce the number of samples and the training time of SVM on large datasets, aiNet is an artificial immune system (AIS) inspired method to perform the automatic data compression, extract the relevant information and retain the topology of the original sample distribution. The output of aiNet is a set of antibodies for representing the input dataset in a simplified way. Then the SVM model is built in the compressed antibody network instead of the original input data. Experimental results show that the ai-SVM algorithm is effective to reduce the computing time and simplify the SVM model, and the accuracy is not decreased.展开更多
Let x 1,x 2,… be independent identically distributed (i.i.d.) random variables, in which x n=0 or 1 and the probability of {x n=1} is p. Here p is unknown. Let τ be any finite stopping ...Let x 1,x 2,… be independent identically distributed (i.i.d.) random variables, in which x n=0 or 1 and the probability of {x n=1} is p. Here p is unknown. Let τ be any finite stopping time for (x n,n1). For any sequential sample (x 1,x 2,…,x τ ) and γ∈(0,1), we have given an optimal confidence limit of p with confidence level γ . Some related problems are also discussed.展开更多
Aimed at the problem of expensive costs in mutation testing which has hampered its wide use,a technique of introducing a test case selection into the process of mutation testing is proposed.For each mutant,a fixed num...Aimed at the problem of expensive costs in mutation testing which has hampered its wide use,a technique of introducing a test case selection into the process of mutation testing is proposed.For each mutant,a fixed number of test cases are selected to constrain the maximum allowable executions so as to reduce useless work.Test case selection largely depends on the degree of mutation.The mutation distance is an index describing the semantic difference between the original program and the mutated program.It represents the percentage of effective test cases in a test set,so it can be used to guide the selection of test cases.The bigger the mutation distance is,the easier it is that the mutant will be killed,so the corresponding number of effective test cases for this mutant is greater.Experimental results suggest that the technique can remarkably reduce execution costs without a significant loss of test effectiveness.展开更多
AIM: To determine the composition of both fecal and duodenal mucosa-associated microbiota in irritable bowel syndrome (IBS) patients and healthy subjects using molecular-based techniques. METHODS: Fecal and duodenal m...AIM: To determine the composition of both fecal and duodenal mucosa-associated microbiota in irritable bowel syndrome (IBS) patients and healthy subjects using molecular-based techniques. METHODS: Fecal and duodenal mucosa brush samples were obtained from 41 IBS patients and 26 healthy subjects. Fecal samples were analyzed for the composition of the total microbiota using fluorescent in situ hybridization (FISH) and both fecal and duodenal brush samples were analyzed for the composition of bif idobacteria using real-time polymerase chain reaction. RESULTS: The FISH analysis of fecal samples revealed a 2-fold decrease in the level of bifidobacteria (4.2 ± 1.3 vs 8.3 ± 1.9, P < 0.01) in IBS patients compared to healthy subjects, whereas no major differences in other bacterial groups were observed. At the species level, Bifidobacterium catenulatum levels were significantly lower (6 ± 0.6 vs 19 ± 2.5, P < 0.001) in the IBS patients in both fecal and duodenal brush samples than in healthy subjects.CONCLUSION: Decreased bifidobacteria levels in both fecal and duodenal brush samples of IBS patients compared to healthy subjects indicate a role for microbiotic composition in IBS pathophysiology.展开更多
Objective To observe the effects of acute normovolemic hemodilution (ANH) on coagulation function and fibrinolysis in elderly patients undergoing hepatic carcinectomy. Methods Thirty elderly patients (aged 60-70 y...Objective To observe the effects of acute normovolemic hemodilution (ANH) on coagulation function and fibrinolysis in elderly patients undergoing hepatic carcinectomy. Methods Thirty elderly patients (aged 60-70 years) with liver cancer (American Society of Anesthesiologists physical status I-II) scheduled for hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group (n= 15) and control group (n= 15). After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch (HES) (130/0.4), and basic liquid containing 6% HES and routine Ringer's solution, respectively. In all the studied patients, blood samples were drawn at five different time points: before anesthesia induction (T1), 30 minutes after ANH (T2), 1 hour after start of operation (T3), immediately after operation (T4), and 24 hours after operation (Ts). Then co- agulation function, soluble fibrin monomer complex (SFMC), prothrombin fragment (F1+2), and platelet membrane glycoprotein (activated GPIIb/GPIIIa and P-selectin) were measured. Results The perioperative blood loss was not significantly different between the two groups (P〉 0.05). The volume of allogeneic blood transfusion in ANH group was significantly smaller than that in control group (350.5±70.7 mL vs. 457.8±181.3 mL, P〈0.01). Compared with the data ofT1, prothrombin time (PT) and activated partial thromboplastin time in both groups prolonged significantly after T3 (P〈0.05), but still within normal range. There were no significant changes in thrombin time and D-dimer between the two groups and between different time points in each group (all P〉0.05). SFMC and F1 +2 increased in both groups, but without statistical significance. P-selectin expression on the platelet surface of ANH group was significantly lowered atT2 andT3 compared with the level atT1 (P〈 0.05). Compared with control group, P-selectin was sig-nificantly lower in ANH group atT2-T3 (all P〈0.05). Conclusions In elderly patients undergoing resection of liver cancer, ANH may not hamper fibri- nolvsis and coagulation function. It coukt therefore be safe to largely reduce allogeneic blood transfusion.展开更多
AIM: To assess the characteristics and quality of endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) in a large panel of endosonographers.METHODS: A survey was conducted during the 13th annual live...AIM: To assess the characteristics and quality of endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) in a large panel of endosonographers.METHODS: A survey was conducted during the 13th annual live course of endoscopic ultrasonography (EUS) held in Amsterdam, Netherlands. A 2-page question- naire was developed for the study. Content validity of the questionnaire was determined based on input by experts in the field and a review of the relevant literature. It contained 30 questions that pertained to demographics and the current practice for EUS-FNA of responders, including sampling technique, sample processing, cytopathological diagnosis and sensitivity of EUS-FNA for the diagnosis of solid mass lesions. One hundred and sixty-one endosonographers whoattended the course were asked to answer the survey. This allowed assessing the current practice of EUS-FNA as well as the self-reported sensitivity of EUS-FNA for the diagnosis of solid mass lesions. We also examined which factors were associated with a self-reported sensitivity of EUS-FNA for the diagnosis of solid mass lesions 〉 80%.RESULTS: Completed surveys were collected from 92 (57.1%) of 161 endosonographers who attended the conference. The endosonographers had been practio ing endoscopy and EUS for 22.5 4. 7.8 years and 4.8 4- 4.1 years, respectively; one third of them worked in a hospital with an annual caseload 〉 100 EUS-FNA. Endoscopy practices were located in 29 countries, in- cluding 13 countries in Western Europe that totaled 75.3% of the responses. Only one third of endosonog raphers reported a sensitivity for the diagnosis of solid mass lesions 〉 80% (interquartile range of sensitivities, 25.0%-75.0%). Factors independently associated with a sensitivity 〉 80% were (1) 〉 7 needle passes for pancreatic lesions or rapid on-site cytopathological evaluation (ROSE) (P 〈 0.0001), (2) a high annual hospital caseload (P = 0.024) and (3) routine isolation of microcores from EUS-FNA samples (P = 0.042). ROSE was routinely available to 27.9% of respondents. For lymph nodes and pancreatic masses, a maximum of three needle passes was performed by approximately two thirds of those who did not have ROSE. Microcores were routinely harvested from EUS-FNA samples by approximately one third (37.2%) of survey respondents.CONCLUSION: EUS-FNA sensitivity was considerably lower than reported in the literature. Low EUS-FNA sensitivity was associated with unavailability of ROSE, few needle passes, absence of microcore isolation and low hospital caseload.展开更多
基金Project(2017G006-N)supported by the Project of Science and Technology Research and Development Program of China Railway Corporation。
文摘Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed bridges.However,the representative temperatures of stayed cables are not specified in the existing design codes.To address this issue,this study investigates the distribution of the cable temperature and determinates its representative temperature.First,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature data.According to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature gradient.Then,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service life.These methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the cables.However,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their application.The proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges.
文摘In order to carry out an integrated assessment of sea water quality objectively, this paper based on the concept and principle of artificial neural network, generated appropriate training samples for BP artificial neural network model through the method of producing samples to the concentration of various pollution index of sea water quality from the viewpoint of threshold, established the BP artificial neural network model of sea water quality assessment using multi-layer neural network with error back-propagation algorithm. This model was used to assess water environment and obtain sea water quality categories of offshore area in Bohai Bay through calculating. The calculations shown that pollution index in river's wet season was higher than that in dry season from 2004 to 2007, and the pollution was particularly serious in 2005 and 2006, but a little better in 2007. The assessed results of cases shown that the model was reasonable in design and higher in generalization, meanwhile, it was common, objective and practical to sea water quality assessment.
基金Project(2011BAE23B05)supported by National Key Technology R&D Program of ChinaProject(61004134)supported by the National Natural Science Foundation of ChinaProject(LQ13F030007)supported by Zhejiang Provincial Natural Science Foundation of China
文摘A vision-based color analysis system was developed for rapid estimation of copper content in the secondary copper smelting process. Firstly, cross section images of secondary copper samples were captured by the designed vision system. After the preprocessing and segmenting procedures, the images were selected according to their grayscale standard deviations of pixels and percentages of edge pixels in the luminance component. The selected images were then used to extract the information of the improved color vector angles, from which the copper content estimation model was developed based on the least squares support vector regression (LSSVR) method. For comparison, three additional LSSVR models, namely, only with sample selection, only with improved color vector angle, without sample selection or improved color vector angle, were developed. In addition, two exponential models, namely, with sample selection, without sample selection, were developed. Experimental results indicate that the proposed method is more effective for improving the copper content estimation accuracy, particularly when the sample size is small.
基金The National Natural Science Foundation of China(No.61231002,61273266,51075068,61271359)Doctoral Fund of Ministry of Education of China(No.20110092130004)
文摘A cascaded projection of the Gaussian mixture model algorithm is proposed.First,the marginal distribution of the Gaussian mixture model is computed for different feature dimensions, and a number of sub-classifiers are generated using the marginal distribution model.Each sub-classifier is based on different feature sets.The cascaded structure is adopted to fuse the sub-classifiers dynamically to achieve sample adaptation ability.Secondly,the effectiveness of the proposed algorithm is verified on electrocardiogram emotional signal and speech emotional signal.Emotional data including fidgetiness,happiness and sadness is collected by induction experiments.Finally,the emotion feature extraction method is discussed,including heart rate variability, the chaotic electrocardiogram feature and utterance level static feature.The emotional feature reduction methods are studied, including principle component analysis,sequential forward selection, the Fisher discriminant ratio and maximal information coefficient.The experimental results show that the proposed classification algorithm can effectively improve recognition accuracy in two different scenarios.
文摘Bagging is not quite suitable for stable classifiers such as nearest neighbor classifiers due to the lack of diversity and it is difficult to be directly applied to face recognition as well due to the small sample size (SSS) property of face recognition. To solve the two problems,local Bagging (L-Bagging) is proposed to simultaneously make Bagging apply to both nearest neighbor classifiers and face recognition. The major difference between L-Bagging and Bagging is that L-Bagging performs the bootstrap sampling on each local region partitioned from the original face image rather than the whole face image. Since the dimensionality of local region is usually far less than the number of samples and the component classifiers are constructed just in different local regions,L-Bagging deals with SSS problem and generates more diverse component classifiers. Experimental results on four standard face image databases (AR,Yale,ORL and Yale B) indicate that the proposed L-Bagging method is effective and robust to illumination,occlusion and slight pose variation.
文摘To study the capacity of artificial neural network (ANN) applying to battlefield target classification and result of classification, according to the characteristics of battlefield target acoustic and seismic signals, an on the spot experiment was carried out to derive acoustic and seismic signals of a tank and jeep by special experiment system. Experiment data processed by fast Fourier transform(FFT) were used to train the ANN to distinguish the two battlefield targets. The ANN classifier was performed by the special program based on the modified back propagation (BP) algorithm. The ANN classifier has high correct identification rates for acoustic and seismic signals of battlefield targets, and is suitable for the classification of battlefield targets. The modified BP algorithm eliminates oscillations and local minimum of the standard BP algorithm, and enhances the convergence rate of the ANN.
文摘Support vector machines (SVMs) are combined with the artificial immune network (aiNet), thus forming a new hybrid ai-SVM algorithm. The algorithm is used to reduce the number of samples and the training time of SVM on large datasets, aiNet is an artificial immune system (AIS) inspired method to perform the automatic data compression, extract the relevant information and retain the topology of the original sample distribution. The output of aiNet is a set of antibodies for representing the input dataset in a simplified way. Then the SVM model is built in the compressed antibody network instead of the original input data. Experimental results show that the ai-SVM algorithm is effective to reduce the computing time and simplify the SVM model, and the accuracy is not decreased.
文摘Let x 1,x 2,… be independent identically distributed (i.i.d.) random variables, in which x n=0 or 1 and the probability of {x n=1} is p. Here p is unknown. Let τ be any finite stopping time for (x n,n1). For any sequential sample (x 1,x 2,…,x τ ) and γ∈(0,1), we have given an optimal confidence limit of p with confidence level γ . Some related problems are also discussed.
基金The National High Technology Research and Development Program of China (863 Program) (No. 2008AA01Z113)the National Natural Science Foundation of China (No. 60773105,60973149)
文摘Aimed at the problem of expensive costs in mutation testing which has hampered its wide use,a technique of introducing a test case selection into the process of mutation testing is proposed.For each mutant,a fixed number of test cases are selected to constrain the maximum allowable executions so as to reduce useless work.Test case selection largely depends on the degree of mutation.The mutation distance is an index describing the semantic difference between the original program and the mutated program.It represents the percentage of effective test cases in a test set,so it can be used to guide the selection of test cases.The bigger the mutation distance is,the easier it is that the mutant will be killed,so the corresponding number of effective test cases for this mutant is greater.Experimental results suggest that the technique can remarkably reduce execution costs without a significant loss of test effectiveness.
文摘AIM: To determine the composition of both fecal and duodenal mucosa-associated microbiota in irritable bowel syndrome (IBS) patients and healthy subjects using molecular-based techniques. METHODS: Fecal and duodenal mucosa brush samples were obtained from 41 IBS patients and 26 healthy subjects. Fecal samples were analyzed for the composition of the total microbiota using fluorescent in situ hybridization (FISH) and both fecal and duodenal brush samples were analyzed for the composition of bif idobacteria using real-time polymerase chain reaction. RESULTS: The FISH analysis of fecal samples revealed a 2-fold decrease in the level of bifidobacteria (4.2 ± 1.3 vs 8.3 ± 1.9, P < 0.01) in IBS patients compared to healthy subjects, whereas no major differences in other bacterial groups were observed. At the species level, Bifidobacterium catenulatum levels were significantly lower (6 ± 0.6 vs 19 ± 2.5, P < 0.001) in the IBS patients in both fecal and duodenal brush samples than in healthy subjects.CONCLUSION: Decreased bifidobacteria levels in both fecal and duodenal brush samples of IBS patients compared to healthy subjects indicate a role for microbiotic composition in IBS pathophysiology.
基金Supported by Ningbo Medical Technology Foundation (200612)
文摘Objective To observe the effects of acute normovolemic hemodilution (ANH) on coagulation function and fibrinolysis in elderly patients undergoing hepatic carcinectomy. Methods Thirty elderly patients (aged 60-70 years) with liver cancer (American Society of Anesthesiologists physical status I-II) scheduled for hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group (n= 15) and control group (n= 15). After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch (HES) (130/0.4), and basic liquid containing 6% HES and routine Ringer's solution, respectively. In all the studied patients, blood samples were drawn at five different time points: before anesthesia induction (T1), 30 minutes after ANH (T2), 1 hour after start of operation (T3), immediately after operation (T4), and 24 hours after operation (Ts). Then co- agulation function, soluble fibrin monomer complex (SFMC), prothrombin fragment (F1+2), and platelet membrane glycoprotein (activated GPIIb/GPIIIa and P-selectin) were measured. Results The perioperative blood loss was not significantly different between the two groups (P〉 0.05). The volume of allogeneic blood transfusion in ANH group was significantly smaller than that in control group (350.5±70.7 mL vs. 457.8±181.3 mL, P〈0.01). Compared with the data ofT1, prothrombin time (PT) and activated partial thromboplastin time in both groups prolonged significantly after T3 (P〈0.05), but still within normal range. There were no significant changes in thrombin time and D-dimer between the two groups and between different time points in each group (all P〉0.05). SFMC and F1 +2 increased in both groups, but without statistical significance. P-selectin expression on the platelet surface of ANH group was significantly lowered atT2 andT3 compared with the level atT1 (P〈 0.05). Compared with control group, P-selectin was sig-nificantly lower in ANH group atT2-T3 (all P〈0.05). Conclusions In elderly patients undergoing resection of liver cancer, ANH may not hamper fibri- nolvsis and coagulation function. It coukt therefore be safe to largely reduce allogeneic blood transfusion.
文摘AIM: To assess the characteristics and quality of endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) in a large panel of endosonographers.METHODS: A survey was conducted during the 13th annual live course of endoscopic ultrasonography (EUS) held in Amsterdam, Netherlands. A 2-page question- naire was developed for the study. Content validity of the questionnaire was determined based on input by experts in the field and a review of the relevant literature. It contained 30 questions that pertained to demographics and the current practice for EUS-FNA of responders, including sampling technique, sample processing, cytopathological diagnosis and sensitivity of EUS-FNA for the diagnosis of solid mass lesions. One hundred and sixty-one endosonographers whoattended the course were asked to answer the survey. This allowed assessing the current practice of EUS-FNA as well as the self-reported sensitivity of EUS-FNA for the diagnosis of solid mass lesions. We also examined which factors were associated with a self-reported sensitivity of EUS-FNA for the diagnosis of solid mass lesions 〉 80%.RESULTS: Completed surveys were collected from 92 (57.1%) of 161 endosonographers who attended the conference. The endosonographers had been practio ing endoscopy and EUS for 22.5 4. 7.8 years and 4.8 4- 4.1 years, respectively; one third of them worked in a hospital with an annual caseload 〉 100 EUS-FNA. Endoscopy practices were located in 29 countries, in- cluding 13 countries in Western Europe that totaled 75.3% of the responses. Only one third of endosonog raphers reported a sensitivity for the diagnosis of solid mass lesions 〉 80% (interquartile range of sensitivities, 25.0%-75.0%). Factors independently associated with a sensitivity 〉 80% were (1) 〉 7 needle passes for pancreatic lesions or rapid on-site cytopathological evaluation (ROSE) (P 〈 0.0001), (2) a high annual hospital caseload (P = 0.024) and (3) routine isolation of microcores from EUS-FNA samples (P = 0.042). ROSE was routinely available to 27.9% of respondents. For lymph nodes and pancreatic masses, a maximum of three needle passes was performed by approximately two thirds of those who did not have ROSE. Microcores were routinely harvested from EUS-FNA samples by approximately one third (37.2%) of survey respondents.CONCLUSION: EUS-FNA sensitivity was considerably lower than reported in the literature. Low EUS-FNA sensitivity was associated with unavailability of ROSE, few needle passes, absence of microcore isolation and low hospital caseload.