A phase Ⅰ/Ⅱ clinical trial for treating malignant melanoma by boron neutron capture therapy(BNCT) was designed to evaluate whether the world's first in-hospital neutron irradiator(IHNI) was qualified for BNCT. ...A phase Ⅰ/Ⅱ clinical trial for treating malignant melanoma by boron neutron capture therapy(BNCT) was designed to evaluate whether the world's first in-hospital neutron irradiator(IHNI) was qualified for BNCT. In this clinical trial planning to enroll 30 patients, the first case was treated on August 19, 2014. We present the protocol of this clinical trial, the treating procedure, and the clinical outcome of this first case. Only grade 2 acute radiation injury was observed during the first four weeks after BNCT and the injury healed after treatment. No late radiation injury was found during the 24-month follow-up. Based on positron emission tomography-computed tomography(PET/CT) scan, pathological analysis and gross examination, the patient showed a complete response to BNCT,indicating that BNCT is a potent therapy against malignant melanoma and IHNI has the potential to enable the delivery of BNCT in hospitals.展开更多
The hot deformation behavior of Ti-22Al-25Nb alloy fabricated by hot compressed sintering was investigated under various conditions of compression tests in the deformation temperature range of 975-1075 °C with 20...The hot deformation behavior of Ti-22Al-25Nb alloy fabricated by hot compressed sintering was investigated under various conditions of compression tests in the deformation temperature range of 975-1075 °C with 20 °C intervals and the strain rate range of 0.001-1.0 s^-1. Based on the experimental data, a novel constitutive relation combining a series of models was developed, including Zener-Hollomon parameter (Z), DRX critical model and kinetics model. The results show that the hot-deformed activation energy Q is calculated to be 410.172 kJ/mol, the ratio of critical strain (εc) to peak strain (εp) is a constant value of about 0.67. The predicted stress obtained by the established constitutive equations matches well with the true stress from experimental data. Despite large errors occur at the stage where strain rate is 0.1 s^-1 and the values of true strain are less than 0.1, the stage of large strain should be more concerned during plastic forming. Furthermore, the predicting accuracy with the DRX kinetics model was testified by an electron back-scattered diffraction (EBSD) technique.展开更多
Objective Dilated cardiomyopathy(DCM) is generally considered to be accompanied by both left and right ventricular dysfunction,but most studies only analyze the left ventricular function. In this study,we evaluated th...Objective Dilated cardiomyopathy(DCM) is generally considered to be accompanied by both left and right ventricular dysfunction,but most studies only analyze the left ventricular function. In this study,we evaluated the effect of arotinolol on right ventricular function in patients with DCM. Methods Right ventricular ejection fraction(RVEF) and right ventricular diameter(RVD) were measured by two-dimensional echocardiography(2-DE) in 33 DCM patients;RVEF measured by first-pass radionuclide angiography(FPRA) was compared with that by 2-DE. Results The treatment with arotinolol for one year resulted in a reduction in the right ventricular diameter(baseline,23.0 ± 8.3 mm vs after one-year treatment,20.7 ± 5.4 mm;P=0.004 ) and an associated increase in ejection fraction(baseline,36.9 ± 10.3% vs after one-year treatment,45.8 ± 9.6%;P < 0.001 ) ;there is a high correlation between the 2-DE method and radionuclide ventriculographic method. The correlation coefficient is 0.933(P<0.001) . Conclusion Arotinolol therapy could not only improve left ventricular function,but also improve right ventricular function in DCM patients.展开更多
Ultrasonic testing(UT)is increasingly combined with machine learning(ML)techniques for intelligently identifying damage.Extracting signifcant features from UT data is essential for efcient defect characterization.More...Ultrasonic testing(UT)is increasingly combined with machine learning(ML)techniques for intelligently identifying damage.Extracting signifcant features from UT data is essential for efcient defect characterization.Moreover,the hidden physics behind ML is unexplained,reducing the generalization capability and versatility of ML methods in UT.In this paper,a generally applicable ML framework based on the model interpretation strategy is proposed to improve the detection accuracy and computational efciency of UT.Firstly,multi-domain features are extracted from the UT signals with signal processing techniques to construct an initial feature space.Subsequently,a feature selection method based on model interpretable strategy(FS-MIS)is innovatively developed by integrating Shapley additive explanation(SHAP),flter method,embedded method and wrapper method.The most efective ML model and the optimal feature subset with better correlation to the target defects are determined self-adaptively.The proposed framework is validated by identifying and locating side-drilled holes(SDHs)with 0.5λcentral distance and different depths.An ultrasonic array probe is adopted to acquire FMC datasets from several aluminum alloy specimens containing two SDHs by experiments.The optimal feature subset selected by FS-MIS is set as the input of the chosen ML model to train and predict the times of arrival(ToAs)of the scattered waves emitted by adjacent SDHs.The experimental results demonstrate that the relative errors of the predicted ToAs are all below 3.67%with an average error of 0.25%,signifcantly improving the time resolution of UT signals.On this basis,the predicted ToAs are assigned to the corresponding original signals for decoupling overlapped pulse-echoes and reconstructing high-resolution FMC datasets.The imaging resolution is enhanced to 0.5λby implementing the total focusing method(TFM).The relative errors of hole depths and central distance are no more than 0.51%and 3.57%,respectively.Finally,the superior performance of the proposed FS-MIS is validated by comparing it with initial feature space and conventional dimensionality reduction techniques.展开更多
The deformation behavior of V-10Cr-5Ti alloy was studied on the Gleeble-1500 thermomechanical simulator at the temperatures of 950-1350℃, and the strain rates of 0.01-10 s^-1. Based on the Arrhenius model, dislocatio...The deformation behavior of V-10Cr-5Ti alloy was studied on the Gleeble-1500 thermomechanical simulator at the temperatures of 950-1350℃, and the strain rates of 0.01-10 s^-1. Based on the Arrhenius model, dislocation density model, nucleation model and grain growth model, a numerical cellular automaton (CA) model coupling simulation of hot deformation is established to simulate and characterize the microstructural evolution during DRX. The results show that the flow stress is fairly sensitive to the strain rate and deformation temperature. The error between the predicted stress by the Arrhenius model and the actual measured value is less than 8%. The initial average grain size calculated by the CA model is 86.25 μm, which is close to the experimental result (85.63 μm). The simulations show that the effect of initial grain size on the dynamic recrystallization microstructure evolution is not significant, while increasing the strain rate or reducing the temperature can refine the recrystallized grains.展开更多
Large and complex construction projects lace risk trom various sources and the successlul completion of such projects depends on effective risk management. This study investigates the risk faced by Chinese firms parti...Large and complex construction projects lace risk trom various sources and the successlul completion of such projects depends on effective risk management. This study investigates the risk faced by Chinese firms participating in constructing AP 1000 nuclear power plants in China. AP 1000 nuclear reactors are new, Generation III+ reactors designed by Westinghouse and to be built first in China. The semi-structured interview approach is used to elicit information from experts involved in the AP1000 projects in China. Based on the interviews, various sources of risk are identified. In addition to general risks that megaprojects normally face, there are unique risks that arise from various sources such as technological, political, organizational, and individual personnel risks. Risk management strategies are proposed to manage general and unique risks identified in the study. The findings of this study would be helpful for Chinese companies involved in the construction of AP 1000 nuclear power plants to mitigate the risks associated with the projects.展开更多
Invasive nonfunctional pituitary adenomas (NFPAs) are difficult to completely resect and often develop tumor recurrence after initial surgery. Currently, no medications are clinically effective in the control of NFP...Invasive nonfunctional pituitary adenomas (NFPAs) are difficult to completely resect and often develop tumor recurrence after initial surgery. Currently, no medications are clinically effective in the control of NFPA. Although radiation therapy and radiosurgery are useful to prevent tumor regrowth, they are frequently withheld because of severe complications. Boron neutron capture therapy (BNCT) is a binary radiotherapy that selectively and maximally damages tumor cells without harming the surrounding normal tissue. Folate receptor (FR)-targeted boron-10 containing carbon nanoparticles is a novel boron delivery agent that can be selectively taken up by FR-expressing cells via FR-mediated endocytosis. In this study, FR-targeted boron-10 containing carbon nanoparticles were selectively taken up by NFPAs cells expressing FR but not other types of non-FR expressing pituitary adenomas. After incubation with boron-10 containing carbon nanoparticles and following irradiation with thermal neutrons, the cell viability of NFPAs was significantly decreased, while apoptotic cells were simultaneously increased. However, cells administered the same dose of FR-targeted boron-10 containing carbon nanoparticles without neutron irradiation or received the same neutron irradiation alone did not show significant decrease in cell viability or increase in apoptotic cells. The expression of Bcl-2 was down-regulated and the expression of Bax was up-regulated in NFPAs after treatment with FR-mediated BNCT. In conclusion, FR-targeted boron-10 containing carbon nanoparticles may be an ideal delivery system of boron to NFPAs ceils for BNCT. Furthermore, our study also provides a novel insight into therapeutic strategies for invasive NFPA refractory to conventional therapy, while exploring these new applications of BNCT for tumors, especially benign tumors.展开更多
Particle size distribution significantly influences the mechanical response of the ballast under low confining pressure.However,particle breakage usually occurs and unfavorably degrades the particle size distribution ...Particle size distribution significantly influences the mechanical response of the ballast under low confining pressure.However,particle breakage usually occurs and unfavorably degrades the particle size distribution of the ballast when sufficient load is applied.To model the triaxial stress-strain behavior and its associated evolution of particle size distribution of the ballast,a specific bounding surface model is proposed.The proposed model is based on the traditional bounding surface plasticity and a modified particle breakage index,which correlates the initial gradation and the ultimate gradation together with the current gradation.Simulation of the experimental results from the triaxial compression tests shows that the proposed model can predict the strain softening and volumetric expansion of the ballast under relatively lower confining pressure.It is also able to simulate the strain hardening and volumetric compression of the ballast under relatively higher confining pressure.Most importantly,the proposed approach was observed to have a great potential in predicting the evolution of the particle size distribution of the ballast.展开更多
Objective: To observe the clinical effect of acupuncture plus tuina on cervical Spondylosis. Method: Altogether 146 cases were randomized into a group of acupuncture plus tuina (observation group) (70 cases), an...Objective: To observe the clinical effect of acupuncture plus tuina on cervical Spondylosis. Method: Altogether 146 cases were randomized into a group of acupuncture plus tuina (observation group) (70 cases), an acupuncture group (control group Ⅰ) (38 cases) and a tuina group (control group Ⅱ) (38 cases). Result: The recovery rate in the observation group, control group I and control group Ⅱ were 92.1%, 68.4% and 65.8% respectively; there was a significant statistical difference between the observation group and two control groups (P〈0.01); and there was no significant statistical difference between the two control groups (P〉0.05). Conclusion: Acupuncture plus tuina can alleviate the patients' condition in a faster and better way.展开更多
Objective:In order to investigate the therapeutic effect of combined adjacent and distal acupoints in the treatment of vertebroarterial pattern of cervical spondylopathy. Methods: 140 cases were randomly divided int...Objective:In order to investigate the therapeutic effect of combined adjacent and distal acupoints in the treatment of vertebroarterial pattern of cervical spondylopathy. Methods: 140 cases were randomly divided into the acupuncture group and medication group, 70 cases in each group. The acupuncture group was treated by the acupoints selected upon TCM pattern identification plus the spots decided upon the anatomical feature in modem medicine. The medication group was treated with oral Dragon Bone Cervical Vertebra Capsules, and Flunarizine Hydrochloride Capsules, to observe the integral of the clinical symptoms and signs and improvement of the vertebrobasilar blood flow before and after the treatment. Results and Conclusion: The total effective rate was significantly higher in the acupuncture group (100%) than in the medication group (61.4%) (P〈 0. 01). There was a significant difference (P〈 0. 05) in the integral of clinical symptoms and sighs and in the improvement of the vertebrobasilar blood flow in comparison between the two groups before and after the treatment, but the improvement was more remarkable in the acupuncture group (P〈 0. 05) than in the medication group, and the long-term therapeutic effect was better in the acupuncture group than in the medication group, but without significant difference (P〉 0. 2).展开更多
基金supported by the National Science&Technology Pillar Program during the 12th Five-Year Plan Period(No.2013BAI01B08)the Major Program of the National Natural Science Foundation of China(No.51290295)
文摘A phase Ⅰ/Ⅱ clinical trial for treating malignant melanoma by boron neutron capture therapy(BNCT) was designed to evaluate whether the world's first in-hospital neutron irradiator(IHNI) was qualified for BNCT. In this clinical trial planning to enroll 30 patients, the first case was treated on August 19, 2014. We present the protocol of this clinical trial, the treating procedure, and the clinical outcome of this first case. Only grade 2 acute radiation injury was observed during the first four weeks after BNCT and the injury healed after treatment. No late radiation injury was found during the 24-month follow-up. Based on positron emission tomography-computed tomography(PET/CT) scan, pathological analysis and gross examination, the patient showed a complete response to BNCT,indicating that BNCT is a potent therapy against malignant melanoma and IHNI has the potential to enable the delivery of BNCT in hospitals.
基金Project(51405110) supported by the National Natural Science Foundation of ChinaProject(2014M551234) supported by the China Postdoctoral Science Foundation+2 种基金Project(20132302120002) supported by the Specialized Research Fund for the Doctoral Program of Higher Education,ChinaProject(HIT.NSRIF.2014006) supported by the Fundamental Research Funds for the Central Universities,ChinaProject(LBH-Z14096) supported by the Heilongjiang Province Postdoctoral Fund,China
文摘The hot deformation behavior of Ti-22Al-25Nb alloy fabricated by hot compressed sintering was investigated under various conditions of compression tests in the deformation temperature range of 975-1075 °C with 20 °C intervals and the strain rate range of 0.001-1.0 s^-1. Based on the experimental data, a novel constitutive relation combining a series of models was developed, including Zener-Hollomon parameter (Z), DRX critical model and kinetics model. The results show that the hot-deformed activation energy Q is calculated to be 410.172 kJ/mol, the ratio of critical strain (εc) to peak strain (εp) is a constant value of about 0.67. The predicted stress obtained by the established constitutive equations matches well with the true stress from experimental data. Despite large errors occur at the stage where strain rate is 0.1 s^-1 and the values of true strain are less than 0.1, the stage of large strain should be more concerned during plastic forming. Furthermore, the predicting accuracy with the DRX kinetics model was testified by an electron back-scattered diffraction (EBSD) technique.
文摘Objective Dilated cardiomyopathy(DCM) is generally considered to be accompanied by both left and right ventricular dysfunction,but most studies only analyze the left ventricular function. In this study,we evaluated the effect of arotinolol on right ventricular function in patients with DCM. Methods Right ventricular ejection fraction(RVEF) and right ventricular diameter(RVD) were measured by two-dimensional echocardiography(2-DE) in 33 DCM patients;RVEF measured by first-pass radionuclide angiography(FPRA) was compared with that by 2-DE. Results The treatment with arotinolol for one year resulted in a reduction in the right ventricular diameter(baseline,23.0 ± 8.3 mm vs after one-year treatment,20.7 ± 5.4 mm;P=0.004 ) and an associated increase in ejection fraction(baseline,36.9 ± 10.3% vs after one-year treatment,45.8 ± 9.6%;P < 0.001 ) ;there is a high correlation between the 2-DE method and radionuclide ventriculographic method. The correlation coefficient is 0.933(P<0.001) . Conclusion Arotinolol therapy could not only improve left ventricular function,but also improve right ventricular function in DCM patients.
基金Supported by National Natural Science Foundation of China(Grant Nos.U22B2068,52275520,52075078)National Key Research and Development Program of China(Grant No.2019YFA0709003).
文摘Ultrasonic testing(UT)is increasingly combined with machine learning(ML)techniques for intelligently identifying damage.Extracting signifcant features from UT data is essential for efcient defect characterization.Moreover,the hidden physics behind ML is unexplained,reducing the generalization capability and versatility of ML methods in UT.In this paper,a generally applicable ML framework based on the model interpretation strategy is proposed to improve the detection accuracy and computational efciency of UT.Firstly,multi-domain features are extracted from the UT signals with signal processing techniques to construct an initial feature space.Subsequently,a feature selection method based on model interpretable strategy(FS-MIS)is innovatively developed by integrating Shapley additive explanation(SHAP),flter method,embedded method and wrapper method.The most efective ML model and the optimal feature subset with better correlation to the target defects are determined self-adaptively.The proposed framework is validated by identifying and locating side-drilled holes(SDHs)with 0.5λcentral distance and different depths.An ultrasonic array probe is adopted to acquire FMC datasets from several aluminum alloy specimens containing two SDHs by experiments.The optimal feature subset selected by FS-MIS is set as the input of the chosen ML model to train and predict the times of arrival(ToAs)of the scattered waves emitted by adjacent SDHs.The experimental results demonstrate that the relative errors of the predicted ToAs are all below 3.67%with an average error of 0.25%,signifcantly improving the time resolution of UT signals.On this basis,the predicted ToAs are assigned to the corresponding original signals for decoupling overlapped pulse-echoes and reconstructing high-resolution FMC datasets.The imaging resolution is enhanced to 0.5λby implementing the total focusing method(TFM).The relative errors of hole depths and central distance are no more than 0.51%and 3.57%,respectively.Finally,the superior performance of the proposed FS-MIS is validated by comparing it with initial feature space and conventional dimensionality reduction techniques.
基金Project(51405110)supported by the National Natural Science Foundation of ChinaProject(20132302120002)supported by the Specialized Research Fund for the Doctoral Program of Higher Education,ChinaProject(LBH-Z14096)supported by Heilongjiang Province Postdoctoral Fund,China
文摘The deformation behavior of V-10Cr-5Ti alloy was studied on the Gleeble-1500 thermomechanical simulator at the temperatures of 950-1350℃, and the strain rates of 0.01-10 s^-1. Based on the Arrhenius model, dislocation density model, nucleation model and grain growth model, a numerical cellular automaton (CA) model coupling simulation of hot deformation is established to simulate and characterize the microstructural evolution during DRX. The results show that the flow stress is fairly sensitive to the strain rate and deformation temperature. The error between the predicted stress by the Arrhenius model and the actual measured value is less than 8%. The initial average grain size calculated by the CA model is 86.25 μm, which is close to the experimental result (85.63 μm). The simulations show that the effect of initial grain size on the dynamic recrystallization microstructure evolution is not significant, while increasing the strain rate or reducing the temperature can refine the recrystallized grains.
文摘Large and complex construction projects lace risk trom various sources and the successlul completion of such projects depends on effective risk management. This study investigates the risk faced by Chinese firms participating in constructing AP 1000 nuclear power plants in China. AP 1000 nuclear reactors are new, Generation III+ reactors designed by Westinghouse and to be built first in China. The semi-structured interview approach is used to elicit information from experts involved in the AP1000 projects in China. Based on the interviews, various sources of risk are identified. In addition to general risks that megaprojects normally face, there are unique risks that arise from various sources such as technological, political, organizational, and individual personnel risks. Risk management strategies are proposed to manage general and unique risks identified in the study. The findings of this study would be helpful for Chinese companies involved in the construction of AP 1000 nuclear power plants to mitigate the risks associated with the projects.
基金supported by the National Natural Science Foundation of China (81072084)
文摘Invasive nonfunctional pituitary adenomas (NFPAs) are difficult to completely resect and often develop tumor recurrence after initial surgery. Currently, no medications are clinically effective in the control of NFPA. Although radiation therapy and radiosurgery are useful to prevent tumor regrowth, they are frequently withheld because of severe complications. Boron neutron capture therapy (BNCT) is a binary radiotherapy that selectively and maximally damages tumor cells without harming the surrounding normal tissue. Folate receptor (FR)-targeted boron-10 containing carbon nanoparticles is a novel boron delivery agent that can be selectively taken up by FR-expressing cells via FR-mediated endocytosis. In this study, FR-targeted boron-10 containing carbon nanoparticles were selectively taken up by NFPAs cells expressing FR but not other types of non-FR expressing pituitary adenomas. After incubation with boron-10 containing carbon nanoparticles and following irradiation with thermal neutrons, the cell viability of NFPAs was significantly decreased, while apoptotic cells were simultaneously increased. However, cells administered the same dose of FR-targeted boron-10 containing carbon nanoparticles without neutron irradiation or received the same neutron irradiation alone did not show significant decrease in cell viability or increase in apoptotic cells. The expression of Bcl-2 was down-regulated and the expression of Bax was up-regulated in NFPAs after treatment with FR-mediated BNCT. In conclusion, FR-targeted boron-10 containing carbon nanoparticles may be an ideal delivery system of boron to NFPAs ceils for BNCT. Furthermore, our study also provides a novel insight into therapeutic strategies for invasive NFPA refractory to conventional therapy, while exploring these new applications of BNCT for tumors, especially benign tumors.
基金supported by the China Scholarship Council in the University of Wollongong(Grant No.201306710022)
文摘Particle size distribution significantly influences the mechanical response of the ballast under low confining pressure.However,particle breakage usually occurs and unfavorably degrades the particle size distribution of the ballast when sufficient load is applied.To model the triaxial stress-strain behavior and its associated evolution of particle size distribution of the ballast,a specific bounding surface model is proposed.The proposed model is based on the traditional bounding surface plasticity and a modified particle breakage index,which correlates the initial gradation and the ultimate gradation together with the current gradation.Simulation of the experimental results from the triaxial compression tests shows that the proposed model can predict the strain softening and volumetric expansion of the ballast under relatively lower confining pressure.It is also able to simulate the strain hardening and volumetric compression of the ballast under relatively higher confining pressure.Most importantly,the proposed approach was observed to have a great potential in predicting the evolution of the particle size distribution of the ballast.
文摘Objective: To observe the clinical effect of acupuncture plus tuina on cervical Spondylosis. Method: Altogether 146 cases were randomized into a group of acupuncture plus tuina (observation group) (70 cases), an acupuncture group (control group Ⅰ) (38 cases) and a tuina group (control group Ⅱ) (38 cases). Result: The recovery rate in the observation group, control group I and control group Ⅱ were 92.1%, 68.4% and 65.8% respectively; there was a significant statistical difference between the observation group and two control groups (P〈0.01); and there was no significant statistical difference between the two control groups (P〉0.05). Conclusion: Acupuncture plus tuina can alleviate the patients' condition in a faster and better way.
文摘Objective:In order to investigate the therapeutic effect of combined adjacent and distal acupoints in the treatment of vertebroarterial pattern of cervical spondylopathy. Methods: 140 cases were randomly divided into the acupuncture group and medication group, 70 cases in each group. The acupuncture group was treated by the acupoints selected upon TCM pattern identification plus the spots decided upon the anatomical feature in modem medicine. The medication group was treated with oral Dragon Bone Cervical Vertebra Capsules, and Flunarizine Hydrochloride Capsules, to observe the integral of the clinical symptoms and signs and improvement of the vertebrobasilar blood flow before and after the treatment. Results and Conclusion: The total effective rate was significantly higher in the acupuncture group (100%) than in the medication group (61.4%) (P〈 0. 01). There was a significant difference (P〈 0. 05) in the integral of clinical symptoms and sighs and in the improvement of the vertebrobasilar blood flow in comparison between the two groups before and after the treatment, but the improvement was more remarkable in the acupuncture group (P〈 0. 05) than in the medication group, and the long-term therapeutic effect was better in the acupuncture group than in the medication group, but without significant difference (P〉 0. 2).