Background:Prediction models for the histological grade of hepatocellular carcinoma(HCC)remain unsatisfactory.The purpose of this study is to develop preoperative models to predict histological grade of HCC based on g...Background:Prediction models for the histological grade of hepatocellular carcinoma(HCC)remain unsatisfactory.The purpose of this study is to develop preoperative models to predict histological grade of HCC based on gadolinium-ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)-enhanced magnetic resonance imaging(MRI)radiomics.And to compare the performance between artificial neural network(ANN)and logistic regression model.Methods:A total of 122 HCCs were randomly assigned to the training set(n=85)and the test set(n=37).There were 242 radiomic features extracted from volumetric of interest(VOI)of arterial and hepatobiliary phases images.The radiomic features and clinical parameters[gender,age,alpha-fetoprotein(AFP),carcinoembryonic antigen(CEA),carbohydrate antigen 19-9(CA19-9),alanine aminotransferase(ALT),aspartate transaminase(AST)]were selected by permutation test and decision tree.ANN of arterial phase(ANN-AP),logistic regression model of arterial phase(LR-AP),ANN of hepatobiliary phase(ANN-HBP),logistic regression mode of hepatobiliary phase(LR-HBP),ANN of combined arterial and hepatobiliary phases(ANN-AP+HBP),and logistic regression model of combined arterial and hepatobiliary phases(LR-AP+HBP)were built to predict HCC histological grade.Those prediction models were assessed and compared.Results:ANN-AP and LR-AP were composed by AST and radiomic features based on arterial phase.ANN-HBP and LR-HBP were composed by AFP and radiomic features based on hepatobiliary phase.ANN-AP+HBP and LR-AP+HBP were composed by AST and radiomic features based on arterial and hepatobiliary phases.The prediction models could distinguish between high-grade tumors[Edmondson-Steiner(E-S)grade III and IV]and low-grade tumors(E-S grade I and II)in both training set and test set.In the test set,the AUCs of ANN-AP,LR-AP,ANN-HBP,LR-HBP,ANN-AP+HBP and LR-AP+HBP were 0.889,0.777,0.941,0.819,0.944 and 0.792 respectively.The ANN-HBP was significantly superior to LR-HBP(P=0.001).And the ANN-AP+HBP was significantly superior to LR展开更多
AIM To evaluate the diagnostic value of gadobenate dimeglumine(Gd-BOPTA)-enhanced hepatocyte-phase magnetic resonance imaging(MRI) in evaluating hepatic fibrosis and hepatitis.METHODS Hepatocyte-phase images of Gd-BOP...AIM To evaluate the diagnostic value of gadobenate dimeglumine(Gd-BOPTA)-enhanced hepatocyte-phase magnetic resonance imaging(MRI) in evaluating hepatic fibrosis and hepatitis.METHODS Hepatocyte-phase images of Gd-BOPTA-enhanced MRI were retrospectively evaluated in 76 patients with chronic liver disease. These patients were classified into five groups according to either the histopathological fibrosis stage(S0-S4) or the histopathological hepatitis grade(G0-G4). The relative enhancement ratio(RE) of the liver parenchyma in the T1-vibe sequence was calculated by measuring the signal intensity before(SI pre) and 90 min after(SI post) intravenous injection of Gd-BOPTA using the following formula: RE =(SI post-SI pre)/SI pre. One-way analysis of variance was used to compare the difference between the relative RE in the hepatocyte phase(REh) and the stage of hepatic fibrosis and the grade of hepatitis. Pearson's productmoment correlation analysis was used to evaluate the relationship between the REh and the levels of serologic liver functional parameters.RESULTS According to histopathological hepatic fibrosis stage, the 76 patients were classified into five groups: 16 in S0, 15 in S1, 21 in S2, 9 in S3, and 15 in S4 group. According to histopathological hepatitis grade, the 76 patients were also classified into five groups: 0 in G0, 44 in G1, 22 in G2, 8 in G3, and 2 in G3 group. With regard to the stage of hepatic fibrosis, REh showed significant differences between the S2 and S3 groups and between the S2 and S4 groups(P < 0.05), but no significant difference was observed between the other groups. With regard to the grade of hepatitis, REh showed significant differences between the G1 and G2 groups and between the G1 and G4 groups(P < 0.05), but no significant difference was observed between the other groups. Increased REh showed correlations with decreased serum levels of TB, ALT and AST(P < 0.05). CONCLUSION To some extent, measuring the REh using Gd-BOPTAenhanced MRI might be a noninvasive technique for assessing展开更多
A small scale thermoacoustic Stirling engine (TASHE) is simulated according to the linear ther-moacoustic theory. The computed results show that in a small scale thermoacoustic Stirling heat en-gine, the diameter of t...A small scale thermoacoustic Stirling engine (TASHE) is simulated according to the linear ther-moacoustic theory. The computed results show that in a small scale thermoacoustic Stirling heat en-gine, the diameter of the resonance tube might have important influences on the working frequency and the performance of the engine, which are always neglected in a large scale system. Likewise, the analysis and experimental results show that in order to obtain better engine performance, the diameter of the resonance tube must be chosen appropriately according to the looped tube dimension and the input heating power. This provides an effective way to miniaturize the thermoacoustic Stirling heat en-gine. According to the computation and analysis, a small scale engine was built, the resonance tube length and diameter of which were about 350 mm and 20 mm, respectively, and the working frequency was about 282 Hz. When the input heating power was about 637 W, the maximal peak to peak pressure amplitude and pressure ratio reached 0.22 MPa and 1.116, respectively, which were able to drive a thermoacoustic refrigerator or an electrical generator.展开更多
BACKGROUND Indentifying predictive factors for postoperative recurrence of hepatocellular carcinoma(HCC)has great significance for patient prognosis.AIM To explore the value of gadolinium ethoxybenzyl diethylenetriami...BACKGROUND Indentifying predictive factors for postoperative recurrence of hepatocellular carcinoma(HCC)has great significance for patient prognosis.AIM To explore the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)enhanced magnetic resonance imaging(MRI)combined with clinical features in predicting early recurrence of HCC after resection.METHODS A total of 161 patients with pathologically confirmed HCC were enrolled.The patients were divided into early recurrence and non-early recurrence group based on the follow-up results.The clinical,laboratory,pathological results and Gd-EOB-DTPA enhanced MRI imaging features were analyzed.RESULTS Of 161 patients,73 had early recurrence and 88 were had non-early recurrence.Univariate analysis showed that patient age,gender,serum alpha-fetoprotein level,the Barcelona Clinic Liver Cancer stage,China liver cancer(CNLC)stage,microvascular invasion(MVI),pathological satellite focus,tumor size,tumor number,tumor boundary,tumor capsule,intratumoral necrosis,portal vein tumor thrombus,large vessel invasion,nonperipheral washout,peritumoral enhancement,hepatobiliary phase(HBP)/tumor signal intensity(SI)/peritumoral SI,HBP peritumoral low signal and peritumoral delay enhancement were significantly associated with early recurrence of HCC after operation.Multivariate logistic regression analysis showed that patient age,MVI,CNLC stage,tumor boundary and large vessel invasion were independent predictive factors.External data validation indicated that the area under the curve of the combined predictors was 0.861,suggesting that multivariate logistic regression was a reasonable predictive model for early recurrence of HCC.CONCLUSION Gd-EOB-DTPA enhanced MRI combined with clinical features would help predicting the early recurrence of HCC after operation.展开更多
The formation and growth of segregation ice dominate the frost heave during soil freezing,which is closely related to water migration.To analyze segregation ice during soil freezing for different soils,a freezing-thaw...The formation and growth of segregation ice dominate the frost heave during soil freezing,which is closely related to water migration.To analyze segregation ice during soil freezing for different soils,a freezing-thawing experiment was conducted with Lanzhou loess(LZL)and Qinghai-Tibet Plateau silty clay(QSC)using a novel layered nuclear magnetic resonance approach.During LZL freezing,the unfrozen water content first increased and then decreased with decreasing temperature near the freezing front,but decreased with decreasing temperature in other layers,whereas during the freezing of QSC,the unfrozen water content in different layers(including the freezing front)decreased with decreased temperature.Notably,the increased liquid water near the freezing front during LZL freezing was primarily adsorbed water.In addition to the temperature gradient,the squeezing action during soil freezing was another important factor affecting water migration,especially at the early stage of soil freezing.However,which of the two factors,squeezing action and temperature gradient,was the dominant one causing water migration depended on soil structure.At the early stage of soil freezing,the squeezing action had a significant effect on the water migration of LZL,but no significant effect on that of QSC.Furthermore,water accumulation of LZL near the freezing front due to squeezing action at the early stage of freezing limited the formation and growth of segregation ice.This study provided an improved understanding for ice segregation and water migration during soil freezing.展开更多
Metamaterials composed of metallic antennae arrays are used as they possess extraordinary optical transmission(EOT)in the terahertz(THz)region,whereby a giant forward light propagation can be created using constructiv...Metamaterials composed of metallic antennae arrays are used as they possess extraordinary optical transmission(EOT)in the terahertz(THz)region,whereby a giant forward light propagation can be created using constructive interference of tunneling surface plasmonic waves.However,numerous applications of THz meta-devices demand an active manipula-tion of the THz beam in free space.Although some studies have been carried out to control the EOT for the THz region,few of these are based upon electrical modulation of the EOT phenomenon,and novel strategies are required for act-ively and dynamically reconfigurable EOT meta-devices.In this work,we experimentally present that the EOT resonance can be coupled to optically reconfigurable chalcogenide metamaterials which offers a reversible all-optical control of the THz light.A modulation efficiency of 88%in transmission at 0.85 THz is experimentally observed using the EOT metama-terials,which is composed of a gold(Au)circular aperture array sitting on a non-volatile chalcogenide phase change ma-terial(Ge2Sb2Te5)film.This comes up with a robust and ultrafast reconfigurable EOT over 20 times of switching,excited by a nanosecond pulsed laser.The measured data have a good agreement with finite-element-method numerical simula-tion.This work promises THz modulators with significant on/off ratios and fast speeds.展开更多
基金This study has received funding by Outstanding Youth supported by Medical Science and Technology Development Foundation Nanjing(JQX16022)Jiangsu Province Key Medical Young Talents,“13th Five-Year”Health Promotion Project of Jiangsu Province(QNRC2016041)+2 种基金The study was conducted in accordance with the Declaration of Helsinki(as revised in 2013)The study was approved by local institutional review board(No.2019AE01036)informed consent from patients was waived due to its retrospective nature。
文摘Background:Prediction models for the histological grade of hepatocellular carcinoma(HCC)remain unsatisfactory.The purpose of this study is to develop preoperative models to predict histological grade of HCC based on gadolinium-ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)-enhanced magnetic resonance imaging(MRI)radiomics.And to compare the performance between artificial neural network(ANN)and logistic regression model.Methods:A total of 122 HCCs were randomly assigned to the training set(n=85)and the test set(n=37).There were 242 radiomic features extracted from volumetric of interest(VOI)of arterial and hepatobiliary phases images.The radiomic features and clinical parameters[gender,age,alpha-fetoprotein(AFP),carcinoembryonic antigen(CEA),carbohydrate antigen 19-9(CA19-9),alanine aminotransferase(ALT),aspartate transaminase(AST)]were selected by permutation test and decision tree.ANN of arterial phase(ANN-AP),logistic regression model of arterial phase(LR-AP),ANN of hepatobiliary phase(ANN-HBP),logistic regression mode of hepatobiliary phase(LR-HBP),ANN of combined arterial and hepatobiliary phases(ANN-AP+HBP),and logistic regression model of combined arterial and hepatobiliary phases(LR-AP+HBP)were built to predict HCC histological grade.Those prediction models were assessed and compared.Results:ANN-AP and LR-AP were composed by AST and radiomic features based on arterial phase.ANN-HBP and LR-HBP were composed by AFP and radiomic features based on hepatobiliary phase.ANN-AP+HBP and LR-AP+HBP were composed by AST and radiomic features based on arterial and hepatobiliary phases.The prediction models could distinguish between high-grade tumors[Edmondson-Steiner(E-S)grade III and IV]and low-grade tumors(E-S grade I and II)in both training set and test set.In the test set,the AUCs of ANN-AP,LR-AP,ANN-HBP,LR-HBP,ANN-AP+HBP and LR-AP+HBP were 0.889,0.777,0.941,0.819,0.944 and 0.792 respectively.The ANN-HBP was significantly superior to LR-HBP(P=0.001).And the ANN-AP+HBP was significantly superior to LR
基金Supported by National Natural Science Foundation of China,Nos.81571784 and 81601471Scientific and Technological Support Project for Social Development of Hunan Province,No.2015SF2020-4Project of Development and Reform Commission of Hunan Province,No.Xiang Cai Enterprise Means[2015]83
文摘AIM To evaluate the diagnostic value of gadobenate dimeglumine(Gd-BOPTA)-enhanced hepatocyte-phase magnetic resonance imaging(MRI) in evaluating hepatic fibrosis and hepatitis.METHODS Hepatocyte-phase images of Gd-BOPTA-enhanced MRI were retrospectively evaluated in 76 patients with chronic liver disease. These patients were classified into five groups according to either the histopathological fibrosis stage(S0-S4) or the histopathological hepatitis grade(G0-G4). The relative enhancement ratio(RE) of the liver parenchyma in the T1-vibe sequence was calculated by measuring the signal intensity before(SI pre) and 90 min after(SI post) intravenous injection of Gd-BOPTA using the following formula: RE =(SI post-SI pre)/SI pre. One-way analysis of variance was used to compare the difference between the relative RE in the hepatocyte phase(REh) and the stage of hepatic fibrosis and the grade of hepatitis. Pearson's productmoment correlation analysis was used to evaluate the relationship between the REh and the levels of serologic liver functional parameters.RESULTS According to histopathological hepatic fibrosis stage, the 76 patients were classified into five groups: 16 in S0, 15 in S1, 21 in S2, 9 in S3, and 15 in S4 group. According to histopathological hepatitis grade, the 76 patients were also classified into five groups: 0 in G0, 44 in G1, 22 in G2, 8 in G3, and 2 in G3 group. With regard to the stage of hepatic fibrosis, REh showed significant differences between the S2 and S3 groups and between the S2 and S4 groups(P < 0.05), but no significant difference was observed between the other groups. With regard to the grade of hepatitis, REh showed significant differences between the G1 and G2 groups and between the G1 and G4 groups(P < 0.05), but no significant difference was observed between the other groups. Increased REh showed correlations with decreased serum levels of TB, ALT and AST(P < 0.05). CONCLUSION To some extent, measuring the REh using Gd-BOPTAenhanced MRI might be a noninvasive technique for assessing
基金the National Natural Science Foundation of China (Grant Nos. 90407012 and 50276064)
文摘A small scale thermoacoustic Stirling engine (TASHE) is simulated according to the linear ther-moacoustic theory. The computed results show that in a small scale thermoacoustic Stirling heat en-gine, the diameter of the resonance tube might have important influences on the working frequency and the performance of the engine, which are always neglected in a large scale system. Likewise, the analysis and experimental results show that in order to obtain better engine performance, the diameter of the resonance tube must be chosen appropriately according to the looped tube dimension and the input heating power. This provides an effective way to miniaturize the thermoacoustic Stirling heat en-gine. According to the computation and analysis, a small scale engine was built, the resonance tube length and diameter of which were about 350 mm and 20 mm, respectively, and the working frequency was about 282 Hz. When the input heating power was about 637 W, the maximal peak to peak pressure amplitude and pressure ratio reached 0.22 MPa and 1.116, respectively, which were able to drive a thermoacoustic refrigerator or an electrical generator.
基金This study was reviewed and approved by the Meizhou People’s Hospital Institutional Review Board(Approval No.2022-C-36).
文摘BACKGROUND Indentifying predictive factors for postoperative recurrence of hepatocellular carcinoma(HCC)has great significance for patient prognosis.AIM To explore the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)enhanced magnetic resonance imaging(MRI)combined with clinical features in predicting early recurrence of HCC after resection.METHODS A total of 161 patients with pathologically confirmed HCC were enrolled.The patients were divided into early recurrence and non-early recurrence group based on the follow-up results.The clinical,laboratory,pathological results and Gd-EOB-DTPA enhanced MRI imaging features were analyzed.RESULTS Of 161 patients,73 had early recurrence and 88 were had non-early recurrence.Univariate analysis showed that patient age,gender,serum alpha-fetoprotein level,the Barcelona Clinic Liver Cancer stage,China liver cancer(CNLC)stage,microvascular invasion(MVI),pathological satellite focus,tumor size,tumor number,tumor boundary,tumor capsule,intratumoral necrosis,portal vein tumor thrombus,large vessel invasion,nonperipheral washout,peritumoral enhancement,hepatobiliary phase(HBP)/tumor signal intensity(SI)/peritumoral SI,HBP peritumoral low signal and peritumoral delay enhancement were significantly associated with early recurrence of HCC after operation.Multivariate logistic regression analysis showed that patient age,MVI,CNLC stage,tumor boundary and large vessel invasion were independent predictive factors.External data validation indicated that the area under the curve of the combined predictors was 0.861,suggesting that multivariate logistic regression was a reasonable predictive model for early recurrence of HCC.CONCLUSION Gd-EOB-DTPA enhanced MRI combined with clinical features would help predicting the early recurrence of HCC after operation.
基金supported by the Key Project of the Natural Science Foundation of China(No.41630636)the National Natural Science Foundation of China(No.41501072)+1 种基金the Independent Foundation of State Key Laboratory of Frozen Soil Engineering,China(No.SKLFSE-ZT-202107)the Natural Science Foundation of Gansu,China(No.22JR5RA057).
文摘The formation and growth of segregation ice dominate the frost heave during soil freezing,which is closely related to water migration.To analyze segregation ice during soil freezing for different soils,a freezing-thawing experiment was conducted with Lanzhou loess(LZL)and Qinghai-Tibet Plateau silty clay(QSC)using a novel layered nuclear magnetic resonance approach.During LZL freezing,the unfrozen water content first increased and then decreased with decreasing temperature near the freezing front,but decreased with decreasing temperature in other layers,whereas during the freezing of QSC,the unfrozen water content in different layers(including the freezing front)decreased with decreased temperature.Notably,the increased liquid water near the freezing front during LZL freezing was primarily adsorbed water.In addition to the temperature gradient,the squeezing action during soil freezing was another important factor affecting water migration,especially at the early stage of soil freezing.However,which of the two factors,squeezing action and temperature gradient,was the dominant one causing water migration depended on soil structure.At the early stage of soil freezing,the squeezing action had a significant effect on the water migration of LZL,but no significant effect on that of QSC.Furthermore,water accumulation of LZL near the freezing front due to squeezing action at the early stage of freezing limited the formation and growth of segregation ice.This study provided an improved understanding for ice segregation and water migration during soil freezing.
文摘Metamaterials composed of metallic antennae arrays are used as they possess extraordinary optical transmission(EOT)in the terahertz(THz)region,whereby a giant forward light propagation can be created using constructive interference of tunneling surface plasmonic waves.However,numerous applications of THz meta-devices demand an active manipula-tion of the THz beam in free space.Although some studies have been carried out to control the EOT for the THz region,few of these are based upon electrical modulation of the EOT phenomenon,and novel strategies are required for act-ively and dynamically reconfigurable EOT meta-devices.In this work,we experimentally present that the EOT resonance can be coupled to optically reconfigurable chalcogenide metamaterials which offers a reversible all-optical control of the THz light.A modulation efficiency of 88%in transmission at 0.85 THz is experimentally observed using the EOT metama-terials,which is composed of a gold(Au)circular aperture array sitting on a non-volatile chalcogenide phase change ma-terial(Ge2Sb2Te5)film.This comes up with a robust and ultrafast reconfigurable EOT over 20 times of switching,excited by a nanosecond pulsed laser.The measured data have a good agreement with finite-element-method numerical simula-tion.This work promises THz modulators with significant on/off ratios and fast speeds.
