AIM: To assess if software assisted-contrast-enhanced ultrasonography (CEUS) provides reproducible perfu- sion parameters of hepatic parenchyma in patients af- fected by chronic liver disease. METHODS: Forty patie...AIM: To assess if software assisted-contrast-enhanced ultrasonography (CEUS) provides reproducible perfu- sion parameters of hepatic parenchyma in patients af- fected by chronic liver disease. METHODS: Forty patients with chronic viral liver dis- ease, with (n = 20) or without (n = 20) cirrhosis, and 10 healthy subjects underwent CEUS and video re- cordings of each examination were then analysed with Esaote's Qontrast software. CEUS dedicated software Qontrast was used to determine peak (the maximum signal intensity), time to peak (TTP), region of blood value (RBV) proportional to the area under the time- intensity curve, mean transit time (MTT) measured in seconds and region of blood flow (RBF). RESULTS: Qontrast-assisted CEUS parameters dis- played high inter-observer reproducibility (κ: coefficients of 0.87 for MTT and 0.90 TTP). When the region of in-terest included a main hepatic vein, Qontrast-calculated TTP was significantly shorter in cirrhotic patients (vs non-cirrhotics and healthy subjects) (71.0 ± 11.3 s vs 82.4±15.6 s, 86.3±20.3 s, P 〈 0.05). MTIs in the patients with liver cirrhosis were significantly shorter than those of controls (111.9±22.0 s vs 139.4±39.8 s, P 〈 0.05), but there was no significant difference between the cirrhotic and non-cirrhotic groups (111.9± 22.0 s vs 110.3 ±14.6 s). Peak enhancement in the patients with liver cirrhosis was also higher than that observed in controls (23.9± 5.9 vs 18.9±7.1, P = 0.05). There were no significant intergroup differences in the RBVs and RBFs. CONCLUSION: Qontrast-assisted CEUS revealed re- producible differences in liver perfusion parameters during the development of hepatic fibrogenesis.展开更多
traditional In this paper, two drawbacks pseudo-static method (vertical of the slice method) in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to...traditional In this paper, two drawbacks pseudo-static method (vertical of the slice method) in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to this method, which is irrational to some extent in the seismic design of slope. Second, only peak ground acceleration (PGA) is considered, and the effects of shaking frequency and duration on slope stability are neglected. And then, based on the theory of elastic wave and the summarized geological model, this paper put forwards an improved method of pseudo-method by using the theory of elastic wave and Hilbert-Huang transform. The improved pseudostatic method gives reasonable considerations to the time-frequency effects of seismic wave and its rationality has been verified by the shaking table test. This method can evaluate the safety of a slope, the happening time and the scale of landslides. At the same time, this method also can improve the high accuracy of the evaluation of the safety of the slope.展开更多
Road network is a critical component of public infrastructure,and the supporting system of social and economic development.Based on a modified kernel density estimate(KDE)algorithm,this study evaluated the road servic...Road network is a critical component of public infrastructure,and the supporting system of social and economic development.Based on a modified kernel density estimate(KDE)algorithm,this study evaluated the road service capacity provided by a road network composed of multi-level roads(i.e.national,provincial,county and rural roads),by taking account of the differences of effect extent and intensity for roads of different levels.Summarized at town scale,the population burden and the annual rural economic income of unit road service capacity were used as the surrogates of social and economic demands for road service.This method was applied to the road network of the Three Parallel River Region,the northwestern Yunnan Province,China to evaluate the development of road network in this region.In results,the total road length of this region in 2005 was 3.70×104km,and the length ratio between national,provincial,county and rural roads was 1∶2∶8∶47.From 1989 to 2005,the regional road service capacity increased by 13.1%,of which the contributions from the national,provincial,county and rural roads were 11.1%,19.4%,22.6%,and 67.8%,respectively,revealing the effect of′All Village Accessible′policy of road development in the mountainous regions in the last decade.The spatial patterns of population burden and economic requirement of unit road service suggested that the areas farther away from the national and provincial roads have higher road development priority(RDP).Based on the modified KDE model and the framework of RDP evaluation,this study provided a useful approach for developing an optimal plan of road development at regional scale.展开更多
Current methods of evaluating long term Sustainable Development seldom take into account the time period over which an evaluation is made except through simplistic economic models which heavily discount the future. If...Current methods of evaluating long term Sustainable Development seldom take into account the time period over which an evaluation is made except through simplistic economic models which heavily discount the future. If sustainable development is to be a serious issue then the impact on the future of decisions made today must be properly assessed and evaluated. This requires a new understanding of time as a key feature of the Sustainability debate and new models of how this new understanding can be brought into the evaluation process. This was at the heart of the Torino declaration signed by the University organisations of the G8, G20 and developing nations in April 2009. Time is a critical part of the sustainability debate and is seldom addressed directly. This paper will provide a possible solution based on a strong theoretical and philosophical framework of how this difficult subject can be approached and applied to sustainable urban planning. The work presented is based on a philosophical model of the cosmos which has both internal and external credibility. It forms the basis ofa PhD study and has been applied to small case studies in Italy and elsewhere. These will be presented to encourage further study into this important area within the evaluation and assessment of sustainable development.展开更多
In order to assess gastric motility, a new noninvasive method was addressed. Firstly, bio-impedance and stomach electric signals were recorded from the healthy control group and the pathologic stomach group. Wavelet t...In order to assess gastric motility, a new noninvasive method was addressed. Firstly, bio-impedance and stomach electric signals were recorded from the healthy control group and the pathologic stomach group. Wavelet transform was used to remove the influence of the heart activity signals. By analyzing and processing the two signals of the time domain and frequency domain, we get the corresponding parameters of the two groups. According to all the parameters, several verification tests have been carried out, from the result of the statistics, we can find that in both time and frequency domains, impedance signal and synchronize EGG (electrogastrogram) have some similar features. However synchronize EGG cannot be totally instead by gastric motility, especially in morbid state, EGG is not correspondence to impedance signal. The gastric contraction or gastric emptying is a complex procedure including electrical and mechanical activity. Electrical impedance (EIP) and the synchronous EGG should be analyzed together. In conclusion, the parameters have the value to evaluate gastric motility.展开更多
基金Supported by Associazione per la Prevenzione e Cure delle Patologie dell’Apparato Digerente-Associazione di Volontariatogrant
文摘AIM: To assess if software assisted-contrast-enhanced ultrasonography (CEUS) provides reproducible perfu- sion parameters of hepatic parenchyma in patients af- fected by chronic liver disease. METHODS: Forty patients with chronic viral liver dis- ease, with (n = 20) or without (n = 20) cirrhosis, and 10 healthy subjects underwent CEUS and video re- cordings of each examination were then analysed with Esaote's Qontrast software. CEUS dedicated software Qontrast was used to determine peak (the maximum signal intensity), time to peak (TTP), region of blood value (RBV) proportional to the area under the time- intensity curve, mean transit time (MTT) measured in seconds and region of blood flow (RBF). RESULTS: Qontrast-assisted CEUS parameters dis- played high inter-observer reproducibility (κ: coefficients of 0.87 for MTT and 0.90 TTP). When the region of in-terest included a main hepatic vein, Qontrast-calculated TTP was significantly shorter in cirrhotic patients (vs non-cirrhotics and healthy subjects) (71.0 ± 11.3 s vs 82.4±15.6 s, 86.3±20.3 s, P 〈 0.05). MTIs in the patients with liver cirrhosis were significantly shorter than those of controls (111.9±22.0 s vs 139.4±39.8 s, P 〈 0.05), but there was no significant difference between the cirrhotic and non-cirrhotic groups (111.9± 22.0 s vs 110.3 ±14.6 s). Peak enhancement in the patients with liver cirrhosis was also higher than that observed in controls (23.9± 5.9 vs 18.9±7.1, P = 0.05). There were no significant intergroup differences in the RBVs and RBFs. CONCLUSION: Qontrast-assisted CEUS revealed re- producible differences in liver perfusion parameters during the development of hepatic fibrogenesis.
基金supported in part by National Science Foundation of China (Contract NO. 41030742)Guangxi Science Foundation and the Program for Science & Technology of Henan Province in China (Grant No. 142300410200)
文摘traditional In this paper, two drawbacks pseudo-static method (vertical of the slice method) in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to this method, which is irrational to some extent in the seismic design of slope. Second, only peak ground acceleration (PGA) is considered, and the effects of shaking frequency and duration on slope stability are neglected. And then, based on the theory of elastic wave and the summarized geological model, this paper put forwards an improved method of pseudo-method by using the theory of elastic wave and Hilbert-Huang transform. The improved pseudostatic method gives reasonable considerations to the time-frequency effects of seismic wave and its rationality has been verified by the shaking table test. This method can evaluate the safety of a slope, the happening time and the scale of landslides. At the same time, this method also can improve the high accuracy of the evaluation of the safety of the slope.
基金Under the auspices of National Natural Science Foundation of China(No.41371190,31021001)Scientific and Tech-nical Projects of Western China Transportation Construction,Ministry of Transport of China(No.2008-318-799-17)
文摘Road network is a critical component of public infrastructure,and the supporting system of social and economic development.Based on a modified kernel density estimate(KDE)algorithm,this study evaluated the road service capacity provided by a road network composed of multi-level roads(i.e.national,provincial,county and rural roads),by taking account of the differences of effect extent and intensity for roads of different levels.Summarized at town scale,the population burden and the annual rural economic income of unit road service capacity were used as the surrogates of social and economic demands for road service.This method was applied to the road network of the Three Parallel River Region,the northwestern Yunnan Province,China to evaluate the development of road network in this region.In results,the total road length of this region in 2005 was 3.70×104km,and the length ratio between national,provincial,county and rural roads was 1∶2∶8∶47.From 1989 to 2005,the regional road service capacity increased by 13.1%,of which the contributions from the national,provincial,county and rural roads were 11.1%,19.4%,22.6%,and 67.8%,respectively,revealing the effect of′All Village Accessible′policy of road development in the mountainous regions in the last decade.The spatial patterns of population burden and economic requirement of unit road service suggested that the areas farther away from the national and provincial roads have higher road development priority(RDP).Based on the modified KDE model and the framework of RDP evaluation,this study provided a useful approach for developing an optimal plan of road development at regional scale.
文摘Current methods of evaluating long term Sustainable Development seldom take into account the time period over which an evaluation is made except through simplistic economic models which heavily discount the future. If sustainable development is to be a serious issue then the impact on the future of decisions made today must be properly assessed and evaluated. This requires a new understanding of time as a key feature of the Sustainability debate and new models of how this new understanding can be brought into the evaluation process. This was at the heart of the Torino declaration signed by the University organisations of the G8, G20 and developing nations in April 2009. Time is a critical part of the sustainability debate and is seldom addressed directly. This paper will provide a possible solution based on a strong theoretical and philosophical framework of how this difficult subject can be approached and applied to sustainable urban planning. The work presented is based on a philosophical model of the cosmos which has both internal and external credibility. It forms the basis ofa PhD study and has been applied to small case studies in Italy and elsewhere. These will be presented to encourage further study into this important area within the evaluation and assessment of sustainable development.
文摘In order to assess gastric motility, a new noninvasive method was addressed. Firstly, bio-impedance and stomach electric signals were recorded from the healthy control group and the pathologic stomach group. Wavelet transform was used to remove the influence of the heart activity signals. By analyzing and processing the two signals of the time domain and frequency domain, we get the corresponding parameters of the two groups. According to all the parameters, several verification tests have been carried out, from the result of the statistics, we can find that in both time and frequency domains, impedance signal and synchronize EGG (electrogastrogram) have some similar features. However synchronize EGG cannot be totally instead by gastric motility, especially in morbid state, EGG is not correspondence to impedance signal. The gastric contraction or gastric emptying is a complex procedure including electrical and mechanical activity. Electrical impedance (EIP) and the synchronous EGG should be analyzed together. In conclusion, the parameters have the value to evaluate gastric motility.