This study explored a new model of Prostate Imaging Reporting and Data System(PIRADS)and adjusted prostate-specific antigen density of peripheral zone(aPSADPZ)for predicting the occurrence of prostate cancer(PCa)and c...This study explored a new model of Prostate Imaging Reporting and Data System(PIRADS)and adjusted prostate-specific antigen density of peripheral zone(aPSADPZ)for predicting the occurrence of prostate cancer(PCa)and clinically significant prostate cancer(csPCa).The demographic and clinical characteristics of 853 patients were recorded.Prostate-specific antigen(PSA),PSA density(PSAD),PSAD of peripheral zone(PSADPZ),aPSADPZ,and peripheral zone volume ratio(PZ-ratio)were calculated and subjected to receiver operating characteristic(ROC)curve analysis.The calibration and discrimination abilities of new nomograms were verified with the calibration curve and area under the ROC curve(AUC).The clinical benefits of these models were evaluated by decision curve analysis and clinical impact curves.The AUCs of PSA,PSAD,PSADPZ,aPSADPZ,and PZ-ratio were 0.669,0.762,0.659,0.812,and 0.748 for PCa diagnosis,while 0.713,0.788,0.694,0.828,and 0.735 for csPCa diagnosis,respectively.All nomograms displayed higher net benefit and better overall calibration than the scenarios for predicting the occurrence of PCa or csPCa.The new model significantly improved the diagnostic accuracy of PCa(0.945 vs 0.830,P<0.01)and csPCa(0.937 vs 0.845,P<0.01)compared with the base model.In addition,the number of patients with PCa and csPCa predicted by the new model was in good agreement with the actual number of patients with PCa and csPCa in high-risk threshold.This study demonstrates that aPSADPZ has a higher predictive accuracy for PCa diagnosis than the conventional indicators.Combining aPSADPZ with PIRADS can improve PCa diagnosis and avoid unnecessary biopsies.展开更多
To improve the diagnostic efficiency of prostate cancer(PCa)and reduce unnecessary biopsies,we defined and analyzed the diagnostic efficiency of peripheral zone prostate-specific antigen(PSA)density(PZ-PSAD).Patients ...To improve the diagnostic efficiency of prostate cancer(PCa)and reduce unnecessary biopsies,we defined and analyzed the diagnostic efficiency of peripheral zone prostate-specific antigen(PSA)density(PZ-PSAD).Patients who underwent systematic 12-core prostate biopsies in Shanghai General Hospital(Shanghai,China)between January 2012 and January 2018 were retrospectively identified(n=529).Another group of patients with benign prostatic hyperplasia(n=100)were randomly preselected to obtain the PSA density of the non-PCa cohort(N-PSAD).Prostate volumes and transition zone volumes were measured using multiparameter magnetic resonance imaging(mpMRI)and were combined with PSA and N-PSAD to obtain the PZ-PSAD from a specific algorithm.Receiver operating characteristic(ROC)curve analysis was used to assess the PCa detection efficiency in patients stratified by PSA level,and the area under the ROC curve(AUC)of PZ-PSAD was higher than that of PSA,PSA density(PSAD),and transition zone PSA density(TZ-PSAD).PZ-PSAD could amend the diagnosis for more than half of the patients with inaccurate transrectal ultrasonography(TRUS)and mpMRI results.When TRUS and mpMRI findings were ambiguous to predict PCa(PIRADS score≤3),PZ-PSAD could increase the positive rate of biopsy from 21.7%to 54.7%,and help 63.8%(150/235)of patients avoid unnecessary prostate biopsy.In patients whose PSA was 4.0–10.0 ng ml^(−1),10.1–20.0 ng ml^(−1),and>20.0 ng ml^(−1),the ideal PZ-PSAD cut-off value for predicting clinically significant PCa was 0.019 ng ml^(−2),0.297 ng ml^(−2),and 1.180 ng ml^(−2),respectively(sensitivity>90%).Compared with PSA,PSAD,and TZ-PSAD,the efficiency of PZ-PSAD for predicting PCa is the highest,leading to fewer missed diagnoses and unnecessary biopsies.展开更多
We modeled the effect of the deformation of a Density Gradient Zone (DGZ) on a local gravity field using a cubical model and introduced a new method to simulate a complex DGZ (CDGZ). Then, we analyzed the features...We modeled the effect of the deformation of a Density Gradient Zone (DGZ) on a local gravity field using a cubical model and introduced a new method to simulate a complex DGZ (CDGZ). Then, we analyzed the features of the model for the influence of the deformation of the DGZ on the local gravity field. We concluded that land-based gravity is not sensitive to the thickness of the DGZ and that the magnitude of the contribution of the DGZ is one order less than that of the volume strain with the same displacement.展开更多
Based on the repeated gravity observation data from 1996 to 2007 from the Longmenshan gravity network, which has been dealt with by adjustment processing, the benchmark interference removal and impact of elevation cha...Based on the repeated gravity observation data from 1996 to 2007 from the Longmenshan gravity network, which has been dealt with by adjustment processing, the benchmark interference removal and impact of elevation changes removal, and by using the 3-D inversion method to reflect underground density, we analyze the characteristics of Longmenshan regional dynamic crustal density at depths of 25km, 20km and 15kin. The results show that in the Wenchuan earthquake preparation process, the regional density field showed marked characteristics both in time and space distribution. From the point of time process, the density change trend in the ten years before the earthquake presents a periodic change pattern: steady phase, dramatic stage, slow reducing phase and slow increase phase. The degree of density changes is from large to small, which means that earthquake gestation has reached the final stage. From the point of space distribution, density change distribution has a tendency of "dispersion--relative concentration", this shows that before the earthquake, the entropy of the underground density field was decreased. In addition, dramatic density changes often occur in the Longmenshan fault zone and western Sichuan plateau. Also, with the increase of depth, the trend of density change is more and more obvious. Through comparative analysis, the influence of density change on gravity is much bigger than that from height change.展开更多
An air dense medium fluidized bed separator(ADMFBS) is used for dry beneficiation of coal using ultrafine magnetite particles as a pseudo-fluid medium. In this process, the coal particle gains additional weight due to...An air dense medium fluidized bed separator(ADMFBS) is used for dry beneficiation of coal using ultrafine magnetite particles as a pseudo-fluid medium. In this process, the coal particle gains additional weight due to coating on its surface and deposition at dead zone area by fine magnetite particles.Hence, the effective density of coal particle increases and the position of coal particle changes accordingly. In this work, an attempt was made to predict the position of coal particle in non-bubbling condition dense medium fluidized bed system. Coal particles of different shape such as cubical, rectangular prism,spherical and triangular prism with different projected area and density were used. The results show that the position of coal particle in air dense medium fluidized bed follows descending order with respect to the increase of density, projected area of coal particle and different shapes(i.e., triangular prism, cubical,rectangular prism and spherical). Empirical mathematical correlations were developed to predict the position of coal particle.展开更多
The aim of this work is to study the influence of successive weld repairs on the microstructure and the mechanical behavior of the heat-affected zone(HAZ) of an HSLA X70 steel. Detailed microstructural examination c...The aim of this work is to study the influence of successive weld repairs on the microstructure and the mechanical behavior of the heat-affected zone(HAZ) of an HSLA X70 steel. Detailed microstructural examination combined to grain size measurement showed that beyond the second weld repair, the microstructure of the HAZ undergoes significant change in the grain morphology and grain growth. The results of the X-ray diffraction analyzed using MAUD software indicated an increase in the crystallite size and a decrease in the dislocation density according to the number of weld repair operations. Consequently, a loss of mechanical properties, namely the yield strength and the toughness with the number of weld repairs, was recorded. Beyond the second weld repair operation, the properties of the welded joint do not fulfill the standards applied in piping industry.展开更多
Damage zones of brittle-ductile (B-D) transition in PP/EPDM blends are studied in this paper. The contribution of crazing and shear yielding zones in damage zones to energy dissipation of blends was measured with comp...Damage zones of brittle-ductile (B-D) transition in PP/EPDM blends are studied in this paper. The contribution of crazing and shear yielding zones in damage zones to energy dissipation of blends was measured with computer image analysis (CIA) and the transition of shear yielding zone (A_(sh)) with rubber volume fraction (V_f) was also manipulated. Results showed that the B-D transition of impact strength of blends corresponded to the fracture mechanism in PP/EPDM blends, from matrix crazing to matrix shear yielding. In addition, two new parameters, density of energy dissipation for crazing zone (F_(cz)) and for shear yielding zone (F_(sh)), are first obtained in this paper. The value of F_(sh) is about four times larger than that of F_(cz) for PP/EPDM blends, which confirmed that the matrix shear yielding is a more effective way of energy dissipation in blends.展开更多
Large olivine samples were hot-pressed synthesized for shock wave experiments. The shock wave experiments were carried out at pressure range between 11 and 42 GPa. Shock data on olivine sample yielded a linear relatio...Large olivine samples were hot-pressed synthesized for shock wave experiments. The shock wave experiments were carried out at pressure range between 11 and 42 GPa. Shock data on olivine sample yielded a linear relationship between shock wave velocity D and particle velocity u described by D=3.56(?0.13)+2.57(?0.12)u. The shock temperature is determined by an energy relationship which is approximately 790°C at pressure 28 GPa. Due to low temperature and short experimental duration, we suggest that no phase change occurred in our sample below 30 GPa and olivine persisted well beyond its equilibrium boundary in metastable phase. The densities of metastable olivine are in agreement with the results of static compression. At the depth shallower than 410 km, the densities of metastable olivine are higher than those of the PREM model, facilitating cold slab to sink into the mantle transition zone. However, in entire mantle transition zone, the shock densities are lower than those of the PREM model, hampering cold slab to flow across the "660 km" phase boundary.展开更多
基金supported by two grants from the Key Research and Development Program of jiangsu Province (No.BE2020654 and No.BE2020655)a grant from the General Program of Jiangsu Health Commission (No.H2019040)a grant from National Key R&D Program of China (No.2017YFC0114303).
文摘This study explored a new model of Prostate Imaging Reporting and Data System(PIRADS)and adjusted prostate-specific antigen density of peripheral zone(aPSADPZ)for predicting the occurrence of prostate cancer(PCa)and clinically significant prostate cancer(csPCa).The demographic and clinical characteristics of 853 patients were recorded.Prostate-specific antigen(PSA),PSA density(PSAD),PSAD of peripheral zone(PSADPZ),aPSADPZ,and peripheral zone volume ratio(PZ-ratio)were calculated and subjected to receiver operating characteristic(ROC)curve analysis.The calibration and discrimination abilities of new nomograms were verified with the calibration curve and area under the ROC curve(AUC).The clinical benefits of these models were evaluated by decision curve analysis and clinical impact curves.The AUCs of PSA,PSAD,PSADPZ,aPSADPZ,and PZ-ratio were 0.669,0.762,0.659,0.812,and 0.748 for PCa diagnosis,while 0.713,0.788,0.694,0.828,and 0.735 for csPCa diagnosis,respectively.All nomograms displayed higher net benefit and better overall calibration than the scenarios for predicting the occurrence of PCa or csPCa.The new model significantly improved the diagnostic accuracy of PCa(0.945 vs 0.830,P<0.01)and csPCa(0.937 vs 0.845,P<0.01)compared with the base model.In addition,the number of patients with PCa and csPCa predicted by the new model was in good agreement with the actual number of patients with PCa and csPCa in high-risk threshold.This study demonstrates that aPSADPZ has a higher predictive accuracy for PCa diagnosis than the conventional indicators.Combining aPSADPZ with PIRADS can improve PCa diagnosis and avoid unnecessary biopsies.
基金This study was supported by the National Natural Science Foundation of China(No.81772746,No.81870516)Natural Science Foundation of Xinjiang Province(2019D01C091).
文摘To improve the diagnostic efficiency of prostate cancer(PCa)and reduce unnecessary biopsies,we defined and analyzed the diagnostic efficiency of peripheral zone prostate-specific antigen(PSA)density(PZ-PSAD).Patients who underwent systematic 12-core prostate biopsies in Shanghai General Hospital(Shanghai,China)between January 2012 and January 2018 were retrospectively identified(n=529).Another group of patients with benign prostatic hyperplasia(n=100)were randomly preselected to obtain the PSA density of the non-PCa cohort(N-PSAD).Prostate volumes and transition zone volumes were measured using multiparameter magnetic resonance imaging(mpMRI)and were combined with PSA and N-PSAD to obtain the PZ-PSAD from a specific algorithm.Receiver operating characteristic(ROC)curve analysis was used to assess the PCa detection efficiency in patients stratified by PSA level,and the area under the ROC curve(AUC)of PZ-PSAD was higher than that of PSA,PSA density(PSAD),and transition zone PSA density(TZ-PSAD).PZ-PSAD could amend the diagnosis for more than half of the patients with inaccurate transrectal ultrasonography(TRUS)and mpMRI results.When TRUS and mpMRI findings were ambiguous to predict PCa(PIRADS score≤3),PZ-PSAD could increase the positive rate of biopsy from 21.7%to 54.7%,and help 63.8%(150/235)of patients avoid unnecessary prostate biopsy.In patients whose PSA was 4.0–10.0 ng ml^(−1),10.1–20.0 ng ml^(−1),and>20.0 ng ml^(−1),the ideal PZ-PSAD cut-off value for predicting clinically significant PCa was 0.019 ng ml^(−2),0.297 ng ml^(−2),and 1.180 ng ml^(−2),respectively(sensitivity>90%).Compared with PSA,PSAD,and TZ-PSAD,the efficiency of PZ-PSAD for predicting PCa is the highest,leading to fewer missed diagnoses and unnecessary biopsies.
基金supported by the Special Earthquake Research Project of China Earthquake Administration(201208009)and the National Natural Science Foundation of China(41274083)
文摘We modeled the effect of the deformation of a Density Gradient Zone (DGZ) on a local gravity field using a cubical model and introduced a new method to simulate a complex DGZ (CDGZ). Then, we analyzed the features of the model for the influence of the deformation of the DGZ on the local gravity field. We concluded that land-based gravity is not sensitive to the thickness of the DGZ and that the magnitude of the contribution of the DGZ is one order less than that of the volume strain with the same displacement.
基金funded by the National Natural Science Foundation of China(41330314)Projects of Science for Earthquake Resilience(XH15049Y)+1 种基金National Science and Technology Support Program of China(2012BAK19B02,2012BAK19B03)Special Research Foundation for Seismology(201108009)
文摘Based on the repeated gravity observation data from 1996 to 2007 from the Longmenshan gravity network, which has been dealt with by adjustment processing, the benchmark interference removal and impact of elevation changes removal, and by using the 3-D inversion method to reflect underground density, we analyze the characteristics of Longmenshan regional dynamic crustal density at depths of 25km, 20km and 15kin. The results show that in the Wenchuan earthquake preparation process, the regional density field showed marked characteristics both in time and space distribution. From the point of time process, the density change trend in the ten years before the earthquake presents a periodic change pattern: steady phase, dramatic stage, slow reducing phase and slow increase phase. The degree of density changes is from large to small, which means that earthquake gestation has reached the final stage. From the point of space distribution, density change distribution has a tendency of "dispersion--relative concentration", this shows that before the earthquake, the entropy of the underground density field was decreased. In addition, dramatic density changes often occur in the Longmenshan fault zone and western Sichuan plateau. Also, with the increase of depth, the trend of density change is more and more obvious. Through comparative analysis, the influence of density change on gravity is much bigger than that from height change.
文摘An air dense medium fluidized bed separator(ADMFBS) is used for dry beneficiation of coal using ultrafine magnetite particles as a pseudo-fluid medium. In this process, the coal particle gains additional weight due to coating on its surface and deposition at dead zone area by fine magnetite particles.Hence, the effective density of coal particle increases and the position of coal particle changes accordingly. In this work, an attempt was made to predict the position of coal particle in non-bubbling condition dense medium fluidized bed system. Coal particles of different shape such as cubical, rectangular prism,spherical and triangular prism with different projected area and density were used. The results show that the position of coal particle in air dense medium fluidized bed follows descending order with respect to the increase of density, projected area of coal particle and different shapes(i.e., triangular prism, cubical,rectangular prism and spherical). Empirical mathematical correlations were developed to predict the position of coal particle.
基金the Research Center in Industria Technologies(CRTI)for its financial supportMohamed Khider University,Biskra,for its help to accomplish this study
文摘The aim of this work is to study the influence of successive weld repairs on the microstructure and the mechanical behavior of the heat-affected zone(HAZ) of an HSLA X70 steel. Detailed microstructural examination combined to grain size measurement showed that beyond the second weld repair, the microstructure of the HAZ undergoes significant change in the grain morphology and grain growth. The results of the X-ray diffraction analyzed using MAUD software indicated an increase in the crystallite size and a decrease in the dislocation density according to the number of weld repair operations. Consequently, a loss of mechanical properties, namely the yield strength and the toughness with the number of weld repairs, was recorded. Beyond the second weld repair operation, the properties of the welded joint do not fulfill the standards applied in piping industry.
基金Project supported by the National Natural Science Foundation of China.
文摘Damage zones of brittle-ductile (B-D) transition in PP/EPDM blends are studied in this paper. The contribution of crazing and shear yielding zones in damage zones to energy dissipation of blends was measured with computer image analysis (CIA) and the transition of shear yielding zone (A_(sh)) with rubber volume fraction (V_f) was also manipulated. Results showed that the B-D transition of impact strength of blends corresponded to the fracture mechanism in PP/EPDM blends, from matrix crazing to matrix shear yielding. In addition, two new parameters, density of energy dissipation for crazing zone (F_(cz)) and for shear yielding zone (F_(sh)), are first obtained in this paper. The value of F_(sh) is about four times larger than that of F_(cz) for PP/EPDM blends, which confirmed that the matrix shear yielding is a more effective way of energy dissipation in blends.
基金the National Natural Science Foundation of China (Grant Nos. 41174074 & 41174073)the Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No. KZCX2-EW-118)
文摘Large olivine samples were hot-pressed synthesized for shock wave experiments. The shock wave experiments were carried out at pressure range between 11 and 42 GPa. Shock data on olivine sample yielded a linear relationship between shock wave velocity D and particle velocity u described by D=3.56(?0.13)+2.57(?0.12)u. The shock temperature is determined by an energy relationship which is approximately 790°C at pressure 28 GPa. Due to low temperature and short experimental duration, we suggest that no phase change occurred in our sample below 30 GPa and olivine persisted well beyond its equilibrium boundary in metastable phase. The densities of metastable olivine are in agreement with the results of static compression. At the depth shallower than 410 km, the densities of metastable olivine are higher than those of the PREM model, facilitating cold slab to sink into the mantle transition zone. However, in entire mantle transition zone, the shock densities are lower than those of the PREM model, hampering cold slab to flow across the "660 km" phase boundary.