BACKGROUND: The indocyanine green (ICG) clearance test (clearance rate (K) and retention rate at 15 minutes (R(15))) is a sensitive indicator to evaluate liver function. The model for end-stage liver disease (MELD) sc...BACKGROUND: The indocyanine green (ICG) clearance test (clearance rate (K) and retention rate at 15 minutes (R(15))) is a sensitive indicator to evaluate liver function. The model for end-stage liver disease (MELD) score has emerged as a useful tool for estimating the mortality of patients awaiting liver transplantation and has recently been validated on patients with liver diseases of various etiologies and severity. In this study, we investigated the correlation between the ICG clearance test and MELD score of patients with liver cirrhosis. METHODS: From June 2007 to March 2008, 52 patients with liver cirrhosis admitted to our center were classified into Child-Pugh class A (8 patients), B (14) and C (30). The ICG clearance test (K value and R(15)) was performed by ICG pulse spectrophotometry (DDG-3300K), and the MELD scores of patients were calculated. RESULTS: As the Child-Pugh classification of liver function gradually deteriorated, the K value decreased, while R(15) and MELD score increased. There were significant statistical differences in K value, R(15) and MELD score in patients with different Child-Pugh classifications. Significant correlations were found between the parameters of the ICG clearance test (K value and R(15)) and MELD score. A negative correlation was observed between K value and MELD score (r=-0.892, P < 0.05), while a positive correlation was observed between R(15) and MELD score (r=0.804, P < 0.05). CONCLUSIONS: The ICG clearance test and MELD score are good parameters for evaluating liver function. Moreover, K value and R(15) have significant correlations with MELD score, especially the K value, which may be a convenient and appropriate indicator to evaluate liver function of patients with liver cirrhosis.展开更多
Estimation of strain-dependent dynamic soil properties, e.g. the shear modulus and damping ratio, along with the liquefaction potential parameters, is extremely important for the assessment and analysis of almost all ...Estimation of strain-dependent dynamic soil properties, e.g. the shear modulus and damping ratio, along with the liquefaction potential parameters, is extremely important for the assessment and analysis of almost all geotechnical problems involving dynamic loading. This paper presents the dynamic properties and liquefaction behaviour of cohesive soil subjected to staged cyclic loading, which may be caused by main shocks of earthquakes preceded or followed by minor foreshocks or aftershocks, respectively. Cyclic triaxial tests were conducted on the specimens prepared at different dry densities (1.5 g/cm3 and 1.75 g/cm3) and different water contents ranging from 8% to 25%. The results indicated that the shear modulus reduction (G/Gmax) and damping ratio of the specimen remain unaffected due to the changes in the initial dry density and water content. Damping ratio is significantly affected by confining pressure, whereas G/Gmax is affected marginally. It was seen that the liquefaction criterion of cohesive soils based on single-amplitude shear strain (3.75% or the strain at which excess pore water pressure ratio becomes equal to 1, whichever is lower) depends on the initial state of soils and applied stresses. The dynamic model of the regional soil, obtained as an outcome of the cyclic triaxial tests, can be successfully used for ground response analysis of the region.展开更多
Cheongpyeong Dam was built in 1943 for the purpose of power generation. Since its construction, discharge flow data based on a theoretical formula have been used to the present times and this leads to a problem of acc...Cheongpyeong Dam was built in 1943 for the purpose of power generation. Since its construction, discharge flow data based on a theoretical formula have been used to the present times and this leads to a problem of accurate discharge flow information not being available. In particular, Cheongpyeong Dam has been partially repaired and modified to maintain the dam structure over a long period of time and is not being properly reflected with changes at the downstream of the river caused by river improvement projects and sedimentation in reservoir. With a goal to improve Cheongpyeong Dam discharge flow calculation, this study aimed at verifying discharge capability and discharge flow by damper opening in relation to the previously suggested discharge flow through a hydraulic model test based on an accurate reproduction of the dam structure and surrounding topographies as in the present conditions. In this study, a hydraulic model test was conducted to examine the discharge flow of Cheongpyeong Dam. In addition, a comparative examination was carried out against the existing discharge flow proposed using theoretical equations. As a verification of the discharge flow of Cheongpyeong Dam, discharge flows in all sluices and a single sluice were examined. Then, the impact of sluice interference caused by the dam structure consisting with 24 sluices was investigated. As a result of the examination, it was found that the difference between discharge flow calculated using the existing theoretical equations and discharge flow derived from the hydraulic model test was insignificant. Based on the results of hydraulic model test, a formula to estimate stage-discharge flow at a sluice was derived and suggested.展开更多
BACKGROUND: Acute liver failure(ALF) is an acute severe deterioration of liver function with high mortality. Early and accurate prognostic assessment of patients with ALF is critically important. Although the model fo...BACKGROUND: Acute liver failure(ALF) is an acute severe deterioration of liver function with high mortality. Early and accurate prognostic assessment of patients with ALF is critically important. Although the model for end-stage liver disease(MELD) scores and King’s College Hospital(KCH) criteria are well-accepted as predictive tools, their accuracy is unsatisfactory.The indocyanine green(ICG) clearance test(ICGR15, ICG retention rate at the 15 minutes) is a sensitive indicator of liver function. In this study, we investigated the efficacy of the ICGR15 for the short-term prognosis in patients with ALF. We compared the predictive value of ICGR15 with the MELD scores and KCH criteria.METHODS: Sixty-nine patients who had been diagnosed with ALF were recruited retrospectively. ICGR15 had been performed by ICG pulse spectrophotometry and relevant clinical and laboratory indices were analyzed within 24 hours of diagnosis.In addition, the MELD scores and KCH criteria were calculated.RESULTS: The three-month mortality of all patients was 47.83%.Age, serum total bilirubin and creatinine concentrations,international normalized ratio for prothrombin time, ICGR15,MELD scores and KCH criteria differed significantly between surviving and deceased patients. A positive correlation was observed between ICGR15 and MELD scores(r=0.328, P=0.006).The ICGR15-MELD model, Logit(P)=0.096×ICGR15+0.174 ×MELD score–9.346, was constructed by logistic regression analysis. The area under the receiver operating characteristic curve was 0.855. When set the cut-off point to-0.4684, the sensitivity was 87.90% and specificity, 72.20%. The area under the receiver operating characteristic curve of the ICGR15-MELD model(0.855) was significantly higher than that of the ICGR15(0.793), MELD scores(0.776) and KCH criteria(0.659).Based on this cut-off value, the patients were divided into two groups. The mortality was 74.36% in the first group(ICGR15-MELD≥-0.4686) and 13.33% in the second group(ICGR15-MELD<-0.4686), with a significant difference between the two groups(χ2=25.307, P=0.000).CONCLUSION: The ICGR15-MELD model is superior to the ICGR15, MELD scores, and KCH criteria in predicting the shortterm prognosis of patients with ALF.展开更多
AIM: To improve the interpretation of fecal immunochemical test (FIT) results in colorectal cancer (CRC) cases from screening and referral cohorts. METHODS: In this comparative observational study, two prospective coh...AIM: To improve the interpretation of fecal immunochemical test (FIT) results in colorectal cancer (CRC) cases from screening and referral cohorts. METHODS: In this comparative observational study, two prospective cohorts of CRC cases were compared. The first cohort was obtained from 10 322 average risk subjects invited for CRC screening with FIT, of which, only subjects with a positive FIT were referred for colonoscopy. The second cohort was obtained from 3637 subjects scheduled for elective colonoscopy with a positive FIT result. The same FIT and positivity threshold (OC sensor; ≥ 50 ng/mL) was used in both cohorts. Colonoscopy was performed in all referral subjects and in FIT positive screening subjects. All CRC cases were selected from both cohorts. Outcome measurements were mean FIT results and FIT scores per tissue tumor stage (T stage). RESULTS: One hundred and eighteen patients with CRC were included in the present study: 28 cases obtained from the screening cohort (64% male; mean age 65 years, SD 6.5) and 90 cases obtained from the referral cohort (58% male; mean age 69 years, SD 9.8). The mean FIT results found were higher in the referral cohort (829 ± 302 ng/mLvs 613 ± 368 ng/mL,P = 0.02). Tissue tumor stage (T stage) distribution was dif-ferent between both populations [screening population: 13 (46%) T1, eight (29%) T2, six (21%) T3, one (4%) T4 carcinoma; referral population: 12 (13%) T1, 22 (24%) T2, 52 (58%) T3, four (4%) T4 carcinoma], and higher T stage was significantly associated with higher FIT results (P < 0.001). Per tumor stage, no significant difference in mean FIT results was observed (screening vs referral: T1 498 ± 382 ng/mL vs 725 ± 374 ng/mL, P = 0.22; T2 787 ± 303 ng/mL vs 794 ± 341 ng/mL, P = 0.79; T3 563 ± 368 ng/mLvs 870 ± 258 ng/mL,P = 0.13; T4 not available). After correction for T stage in logistic regression analysis, no significant differences in mean FIT results were observed between both types of cohorts (P = 0.10). CONCLUSION: Differences in T stage distribution largely explain differences in FIT results between screening and referral cohorts. Therefore, FIT results should be reported according to T stage.展开更多
In this paper, we propose the test statistic to check whether the nonparametric function in partially linear models is linear or not. We estimate the nonparametric function in alternative by using the local linear met...In this paper, we propose the test statistic to check whether the nonparametric function in partially linear models is linear or not. We estimate the nonparametric function in alternative by using the local linear method, and then estimate the parameters by the two stage method. The test statistic under the null hypothesis is calculated, and it is shown to be asymptotically normal.展开更多
In order to investigate the aerodynamic behavior of the Sutong bridge over Yangtze River during erection, a 1:50 sectional model of the bridge deck, a 1: 100 full aeroelastic model of the free standing pylon and a 1...In order to investigate the aerodynamic behavior of the Sutong bridge over Yangtze River during erection, a 1:50 sectional model of the bridge deck, a 1: 100 full aeroelastic model of the free standing pylon and a 1: 125 full aeroelastic model for the maxim cantilever configuration were built. The test results show that there was no serious vortex-induced vibration at the bridge deck, and that the free standing tower, the model scale and the turbulence intensity influenced static loading. The buffeting responses during the maximum cantilever configuration did not affect the safety of the bridge under construction.展开更多
We propose the test statistic to check whether the nonpararnetric functions in two partially linear models are equality or not in this paper. We estimate the nonparametric function both in null hypothesis and the alte...We propose the test statistic to check whether the nonpararnetric functions in two partially linear models are equality or not in this paper. We estimate the nonparametric function both in null hypothesis and the alternative by the local linear method, where we ignore the parametric components, and then estimate the parameters by the two stage method. The test statistic is derived, and it is shown to be asymptotically normal under the null hypothesis.展开更多
The necessity of underground coal gasification is explained. The condition,technology character,and process of the semi-industrial test of underground coal gasification in well No. 2 at Xinhe, Xuzhou,are introduced. T...The necessity of underground coal gasification is explained. The condition,technology character,and process of the semi-industrial test of underground coal gasification in well No. 2 at Xinhe, Xuzhou,are introduced. The test results indicate that the technique of long tunnel,large sectiou,two stage underground coal gasification can obtain a large output of coal gas with a high heat value, making the working process stable. So the feasibility of the new techuology is verified. It can be concluded that there will have a good application prospect of the technique in China.展开更多
文摘BACKGROUND: The indocyanine green (ICG) clearance test (clearance rate (K) and retention rate at 15 minutes (R(15))) is a sensitive indicator to evaluate liver function. The model for end-stage liver disease (MELD) score has emerged as a useful tool for estimating the mortality of patients awaiting liver transplantation and has recently been validated on patients with liver diseases of various etiologies and severity. In this study, we investigated the correlation between the ICG clearance test and MELD score of patients with liver cirrhosis. METHODS: From June 2007 to March 2008, 52 patients with liver cirrhosis admitted to our center were classified into Child-Pugh class A (8 patients), B (14) and C (30). The ICG clearance test (K value and R(15)) was performed by ICG pulse spectrophotometry (DDG-3300K), and the MELD scores of patients were calculated. RESULTS: As the Child-Pugh classification of liver function gradually deteriorated, the K value decreased, while R(15) and MELD score increased. There were significant statistical differences in K value, R(15) and MELD score in patients with different Child-Pugh classifications. Significant correlations were found between the parameters of the ICG clearance test (K value and R(15)) and MELD score. A negative correlation was observed between K value and MELD score (r=-0.892, P < 0.05), while a positive correlation was observed between R(15) and MELD score (r=0.804, P < 0.05). CONCLUSIONS: The ICG clearance test and MELD score are good parameters for evaluating liver function. Moreover, K value and R(15) have significant correlations with MELD score, especially the K value, which may be a convenient and appropriate indicator to evaluate liver function of patients with liver cirrhosis.
文摘Estimation of strain-dependent dynamic soil properties, e.g. the shear modulus and damping ratio, along with the liquefaction potential parameters, is extremely important for the assessment and analysis of almost all geotechnical problems involving dynamic loading. This paper presents the dynamic properties and liquefaction behaviour of cohesive soil subjected to staged cyclic loading, which may be caused by main shocks of earthquakes preceded or followed by minor foreshocks or aftershocks, respectively. Cyclic triaxial tests were conducted on the specimens prepared at different dry densities (1.5 g/cm3 and 1.75 g/cm3) and different water contents ranging from 8% to 25%. The results indicated that the shear modulus reduction (G/Gmax) and damping ratio of the specimen remain unaffected due to the changes in the initial dry density and water content. Damping ratio is significantly affected by confining pressure, whereas G/Gmax is affected marginally. It was seen that the liquefaction criterion of cohesive soils based on single-amplitude shear strain (3.75% or the strain at which excess pore water pressure ratio becomes equal to 1, whichever is lower) depends on the initial state of soils and applied stresses. The dynamic model of the regional soil, obtained as an outcome of the cyclic triaxial tests, can be successfully used for ground response analysis of the region.
文摘Cheongpyeong Dam was built in 1943 for the purpose of power generation. Since its construction, discharge flow data based on a theoretical formula have been used to the present times and this leads to a problem of accurate discharge flow information not being available. In particular, Cheongpyeong Dam has been partially repaired and modified to maintain the dam structure over a long period of time and is not being properly reflected with changes at the downstream of the river caused by river improvement projects and sedimentation in reservoir. With a goal to improve Cheongpyeong Dam discharge flow calculation, this study aimed at verifying discharge capability and discharge flow by damper opening in relation to the previously suggested discharge flow through a hydraulic model test based on an accurate reproduction of the dam structure and surrounding topographies as in the present conditions. In this study, a hydraulic model test was conducted to examine the discharge flow of Cheongpyeong Dam. In addition, a comparative examination was carried out against the existing discharge flow proposed using theoretical equations. As a verification of the discharge flow of Cheongpyeong Dam, discharge flows in all sluices and a single sluice were examined. Then, the impact of sluice interference caused by the dam structure consisting with 24 sluices was investigated. As a result of the examination, it was found that the difference between discharge flow calculated using the existing theoretical equations and discharge flow derived from the hydraulic model test was insignificant. Based on the results of hydraulic model test, a formula to estimate stage-discharge flow at a sluice was derived and suggested.
基金supported by a grant from the Foundation of the Ministry of Health,China(2008ZX1005)
文摘BACKGROUND: Acute liver failure(ALF) is an acute severe deterioration of liver function with high mortality. Early and accurate prognostic assessment of patients with ALF is critically important. Although the model for end-stage liver disease(MELD) scores and King’s College Hospital(KCH) criteria are well-accepted as predictive tools, their accuracy is unsatisfactory.The indocyanine green(ICG) clearance test(ICGR15, ICG retention rate at the 15 minutes) is a sensitive indicator of liver function. In this study, we investigated the efficacy of the ICGR15 for the short-term prognosis in patients with ALF. We compared the predictive value of ICGR15 with the MELD scores and KCH criteria.METHODS: Sixty-nine patients who had been diagnosed with ALF were recruited retrospectively. ICGR15 had been performed by ICG pulse spectrophotometry and relevant clinical and laboratory indices were analyzed within 24 hours of diagnosis.In addition, the MELD scores and KCH criteria were calculated.RESULTS: The three-month mortality of all patients was 47.83%.Age, serum total bilirubin and creatinine concentrations,international normalized ratio for prothrombin time, ICGR15,MELD scores and KCH criteria differed significantly between surviving and deceased patients. A positive correlation was observed between ICGR15 and MELD scores(r=0.328, P=0.006).The ICGR15-MELD model, Logit(P)=0.096×ICGR15+0.174 ×MELD score–9.346, was constructed by logistic regression analysis. The area under the receiver operating characteristic curve was 0.855. When set the cut-off point to-0.4684, the sensitivity was 87.90% and specificity, 72.20%. The area under the receiver operating characteristic curve of the ICGR15-MELD model(0.855) was significantly higher than that of the ICGR15(0.793), MELD scores(0.776) and KCH criteria(0.659).Based on this cut-off value, the patients were divided into two groups. The mortality was 74.36% in the first group(ICGR15-MELD≥-0.4686) and 13.33% in the second group(ICGR15-MELD<-0.4686), with a significant difference between the two groups(χ2=25.307, P=0.000).CONCLUSION: The ICGR15-MELD model is superior to the ICGR15, MELD scores, and KCH criteria in predicting the shortterm prognosis of patients with ALF.
基金Supported by A Research Grant of Center for Translational Molecular Medicine, The Netherlands, to van Turenhout STGrant of Nycomed B.V., Hoofddorp to "the Amsterdam Gut-club", The Netherlands+1 种基金The Netherlands Organization for Health Research and Development, ZonMW, No. 50-50115-98-060,project 63000004The original trial was registered under IS-RCTN57917442 at Current Controlled Trials (www.controlled-trials.com)
文摘AIM: To improve the interpretation of fecal immunochemical test (FIT) results in colorectal cancer (CRC) cases from screening and referral cohorts. METHODS: In this comparative observational study, two prospective cohorts of CRC cases were compared. The first cohort was obtained from 10 322 average risk subjects invited for CRC screening with FIT, of which, only subjects with a positive FIT were referred for colonoscopy. The second cohort was obtained from 3637 subjects scheduled for elective colonoscopy with a positive FIT result. The same FIT and positivity threshold (OC sensor; ≥ 50 ng/mL) was used in both cohorts. Colonoscopy was performed in all referral subjects and in FIT positive screening subjects. All CRC cases were selected from both cohorts. Outcome measurements were mean FIT results and FIT scores per tissue tumor stage (T stage). RESULTS: One hundred and eighteen patients with CRC were included in the present study: 28 cases obtained from the screening cohort (64% male; mean age 65 years, SD 6.5) and 90 cases obtained from the referral cohort (58% male; mean age 69 years, SD 9.8). The mean FIT results found were higher in the referral cohort (829 ± 302 ng/mLvs 613 ± 368 ng/mL,P = 0.02). Tissue tumor stage (T stage) distribution was dif-ferent between both populations [screening population: 13 (46%) T1, eight (29%) T2, six (21%) T3, one (4%) T4 carcinoma; referral population: 12 (13%) T1, 22 (24%) T2, 52 (58%) T3, four (4%) T4 carcinoma], and higher T stage was significantly associated with higher FIT results (P < 0.001). Per tumor stage, no significant difference in mean FIT results was observed (screening vs referral: T1 498 ± 382 ng/mL vs 725 ± 374 ng/mL, P = 0.22; T2 787 ± 303 ng/mL vs 794 ± 341 ng/mL, P = 0.79; T3 563 ± 368 ng/mLvs 870 ± 258 ng/mL,P = 0.13; T4 not available). After correction for T stage in logistic regression analysis, no significant differences in mean FIT results were observed between both types of cohorts (P = 0.10). CONCLUSION: Differences in T stage distribution largely explain differences in FIT results between screening and referral cohorts. Therefore, FIT results should be reported according to T stage.
文摘In this paper, we propose the test statistic to check whether the nonparametric function in partially linear models is linear or not. We estimate the nonparametric function in alternative by using the local linear method, and then estimate the parameters by the two stage method. The test statistic under the null hypothesis is calculated, and it is shown to be asymptotically normal.
基金The National Natural Science Foundation of China(Nos.50808148 and 90815016)
文摘In order to investigate the aerodynamic behavior of the Sutong bridge over Yangtze River during erection, a 1:50 sectional model of the bridge deck, a 1: 100 full aeroelastic model of the free standing pylon and a 1: 125 full aeroelastic model for the maxim cantilever configuration were built. The test results show that there was no serious vortex-induced vibration at the bridge deck, and that the free standing tower, the model scale and the turbulence intensity influenced static loading. The buffeting responses during the maximum cantilever configuration did not affect the safety of the bridge under construction.
文摘We propose the test statistic to check whether the nonpararnetric functions in two partially linear models are equality or not in this paper. We estimate the nonparametric function both in null hypothesis and the alternative by the local linear method, where we ignore the parametric components, and then estimate the parameters by the two stage method. The test statistic is derived, and it is shown to be asymptotically normal under the null hypothesis.
文摘The necessity of underground coal gasification is explained. The condition,technology character,and process of the semi-industrial test of underground coal gasification in well No. 2 at Xinhe, Xuzhou,are introduced. The test results indicate that the technique of long tunnel,large sectiou,two stage underground coal gasification can obtain a large output of coal gas with a high heat value, making the working process stable. So the feasibility of the new techuology is verified. It can be concluded that there will have a good application prospect of the technique in China.