The effect of hydrostatic pressure on the vibration dispersion characteristics of fluid-shell coupled structures was studied.Both fluid-loaded cylindrical shells and fluid-filled cylindrical shells were considered.Num...The effect of hydrostatic pressure on the vibration dispersion characteristics of fluid-shell coupled structures was studied.Both fluid-loaded cylindrical shells and fluid-filled cylindrical shells were considered.Numerical analysis was applied to solve the dispersion equations for shells filled with or loaded with fluid at various hydrostatic pressures.The results for external pressure showed that non-dimensional axial wave numbers are nearly independent when the pressure is below the critical level.The influence of internal pressure on wave numbers was found significant for the real branch s=1 and the complex branches of dispersion curves.The presence of internal pressure increased the cut on frequencies for the branch s=1 for high order wave modes.展开更多
Vehicle detectition in still images is a comparatively difficult task. This paper presents a method for this task by using boosted local pattern detector constructed from two local features including Haar-like and ori...Vehicle detectition in still images is a comparatively difficult task. This paper presents a method for this task by using boosted local pattern detector constructed from two local features including Haar-like and oriented gradient features. The whole process is composed of three stages. In the first stage, local appearance features of vehicles and non-vehicle objects are extracted. Haar-tike and oriented gradient features are extracted separately in this stage as local features. In the second stage, Adabeost algorithm is used to select the most discriminative features as weak detectors from the two local feature sets, and a strong local pattern detector is built by the weighted combination of these selected weak detectors. Finally, vehicle detection can be performed in still images by using the boosted strong local feature detector. Experiment results show that the local pattern detector constructed in this way combines the advantages of Haar-like and oriented gradient features, and can achieve better detection results than the detector by using single Haar-like features.展开更多
AIM: To examine whether the sedative effects assessed by psychomotor tests would depend on the cytochrome P450 (CYP ) 2C19 genotypes after an infusion regimen of diazepam commonly used forgastrointestinal endoscopy in...AIM: To examine whether the sedative effects assessed by psychomotor tests would depend on the cytochrome P450 (CYP ) 2C19 genotypes after an infusion regimen of diazepam commonly used forgastrointestinal endoscopy in Japan. METHODS: Fifteen healthy Japanese volunteers consisting of three different CYP2C19 genotype groups underwent a critical ? icker fusion test, an eye movement analysis and a postural sway test as a test for physical sedative effects, and a visual analog scale (VAS) symptom assessment method as a test for mental sedative effects during the 336 h period after the intravenous infusion of diazepam (5 mg). RESULTS: The physical sedative effects assessed by the critical flicker test continued for 1 h (t values of 5 min, 30 min and 60 min later: 4.35, 5.00 and 3.19, respectively) and those by the moving radial area of a postural sway test continued for 3 h (t values of 5 h, 30 h, 60 min and 3 h later: -4.05, -3.42, -2.17 and -2.58, respectively), which changed significantly compared with the baseline level before infusion (P < 0.05). On the other hand, the mental sedative effects by the VAS method improved within 1 h. The CYP2C19 genotype-dependent differences in the postinfusion sedative effects were not observed in any of the four psychomotor function tests. CONCLUSION: With the psychomotor tests, the objective sedative effects of diazepam continued for 1 h to 3 h irrespective of CYP2C19 genotype status and the subjective sedative symptoms improved within 1 h. Up to 3 h of clinical care appears to be required after the infusion of diazepam, although patients feel subjectively improved.展开更多
A new structural damage identification method using limited test static displacement based on grey system theory is proposed in this paper. The grey relation coefficient of displacement curvature is defined and used t...A new structural damage identification method using limited test static displacement based on grey system theory is proposed in this paper. The grey relation coefficient of displacement curvature is defined and used to locate damage in the structure, and an iterative estimation scheme for solving nonlinear optimization programming problems based on the quadratic programming technique is used to identify the damage magnitude. A numerical example of a cantilever beam with single or multiple damages is used to examine the capability of the proposed grey-theory-based method to localize and identify damages. The factors of meas-urement noise and incomplete test data are also discussed. The numerical results showed that the damage in the structure can be localized correctly through using the grey-related coefficient of displacement curvature, and the damage magnitude can be iden-tified with a high degree of accuracy, regardless of the number of measured displacement nodes. This proposed method only requires limited static test data, which is easily available in practice, and has wide applications in structural damage detection.展开更多
Objective. To evaluate the diagnostic criteria for the localization of acquired arteriovenous fistulas (AVFs) by color Doppler flow imaging (CDFI) based on the features of their hemodynamic changes. Methods. The shape...Objective. To evaluate the diagnostic criteria for the localization of acquired arteriovenous fistulas (AVFs) by color Doppler flow imaging (CDFI) based on the features of their hemodynamic changes. Methods. The shape and hemodynamic changes of involved vessels which could be helpful to localize the sites of fistulas were studied according to the observation of 10 cases of acquired AVFs. Results. The sites of the fistulas could be shown by two dimensional ultrasonography and color flow imaging in 40%and 80%cases, respectively. In all cases, turbulent high velocity flow was present at the sites of the fistulas, low resistant flow was present in the arteries proximal to the fistulas, and artery like flow was detected in the veins. Conclusion. CDFI was accurate for the localization of acquired AVFs, which were mainly localized by their hemodynamic changes shown by pulse Doppler ultrasound.展开更多
AIM:To review percutaneous transhepatic portal venoplasty and stenting(PTPVS)for portal vein anastomotic stenosis(PVAS)after liver transplantation (LT). METHODS:From April 2004 to June 2008,16 of 18 consecutive patien...AIM:To review percutaneous transhepatic portal venoplasty and stenting(PTPVS)for portal vein anastomotic stenosis(PVAS)after liver transplantation (LT). METHODS:From April 2004 to June 2008,16 of 18 consecutive patients(11 male and 5 female;aged 17-66 years,mean age 40.4 years)underwent PTPVS for PVAS.PVAS occurred 2-10 mo after LT(mean 5.0 mo). Three asymptomatic patients were detected on routine screening color Doppler ultrasonography(CDUS). Fifteen patients who also had typical clinical signs of portal hypertension(PHT)were identified by contrastenhanced computerized tomography(CT)or magnetic resonance imaging.All procedures were performed under local anesthesia.If there was a PVAS<75%, the portal pressure was measured.Portal venoplasty was performed with an undersized balloon and slowly inflated.All stents were deployed immediately following the predilation.Follow-ups,including clinical course, stenosis recurrence and stent patency which were evaluated by CDUS and CT,were performed. RESULTS:Technical success was achieved in all patients.No procedure-related complications occurred. Liver function was normalized gradually and the symptoms of PHT also improved following PTPVS.In 2 of 3 asymptomatic patients,portal venoplasty and stenting were not performed because of pressure gradients<5 mmHg.They were observed with periodic CDUS or CT.PTPVS was performed in 16 patients.In 2 patients,the mean pressure gradients decreased from 15.5 mmHg to 3.0 mmHg.In the remaining 14 patients,a pressure gradient was not obtained because of>75%stenosis and typical clinical signs of PHT.In a 51-year-old woman,who suffered from massive ascites and severe bilateral lower limb edema after secondary LT,PVAS complicated hepatic vein stenosis and inferior vena cava(IVC)stenosis. Before PTPVS,a self-expandable and a balloonexpandable metallic stent were deployed in the IVC and right hepatic vein respectively.The ascites and edema resolved gradually after treatment.The portosystemic collateral vessels resulting from PHT were visualized in 14 patients.Gastroesophageal varices became invisible on poststenting portography in 9 patients.In a 28-yearold man with hepatic encephalopathy,a pre-existing meso-caval shunt was detected due to visualization of IVC on portography.After stenting,contrast agents flowed mainly into IVC via the shunt and little flowed into the portal vein.A covered stent was deployed into the superior mesenteric vein to occlude the shunt. Portal hepatopetal flow was restored and the IVC became invisible.The patient recovered from hepatic encephalopathy.A balloon-expandable Palmaz stent was deployed into hepatic artery for anastomotic stenosis before PTPVS.Percutaneous transhepatic internal-external biliary drainage was performed in 2 patients with obstructive jaundice.Portal venous patency was maintained for 3.3-56.6 mo(mean 33.0 mo) and all patients remained asymptomatic.CONCLUSION:With technical refinements,early detection and prompt treatment of complications,and advances in immunotherapy,excellent results can be achieved in LT.展开更多
Using the third-order WKB approximation, we evaluate the quasinormal frequencies of massless Dirac field perturbation around a Reissner Nordstrom black hole surrounded by a static and spherically symmetric quintessenc...Using the third-order WKB approximation, we evaluate the quasinormal frequencies of massless Dirac field perturbation around a Reissner Nordstrom black hole surrounded by a static and spherically symmetric quintessence. We study the variation of quasinormal frequencies with the quintessential state parameter ε, the total angular momentum number |k|, the charge Q, and the overtone number n changes, respectively. Moreover, from the results we obtained, we find that the massless Dirac field damps more slowly due to the presence of quintessence.展开更多
Increasing reports on application and safety of liposomal amphotericin B (Amphotec) in the treatment of deep fungal infections have been described recently. This is the first report that a case of liver abscess due to...Increasing reports on application and safety of liposomal amphotericin B (Amphotec) in the treatment of deep fungal infections have been described recently. This is the first report that a case of liver abscess due to Candida albicans was completely cured with intra-abscess and intravenous administration of liposomal amphotericin B without recurrence in three-year follow-up period.展开更多
By using the quantum magnetohydrodynamic model, the electrostatic waves in weakly magnetized quantum plasmas are investigated. The electrons are treated as a quantum and magnetized species, while the ions are classica...By using the quantum magnetohydrodynamic model, the electrostatic waves in weakly magnetized quantum plasmas are investigated. The electrons are treated as a quantum and magnetized species, while the ions are classical unmagnetized ones. The general dispersion relations are derived. It is shown that, both the high frequency electron waves (Langmuire wave and upper-hybrid wave) and the low frequency ion acoustic wave can propagate when the plasmas are cold.展开更多
Black lenses with L(n,1) horizon topology in five dimensions have many unusual properties shared by neither Myers-Perry black holes with event-horizon topology S 3,nor 5-dimensional black rings with event-horizon topo...Black lenses with L(n,1) horizon topology in five dimensions have many unusual properties shared by neither Myers-Perry black holes with event-horizon topology S 3,nor 5-dimensional black rings with event-horizon topology S 2 × S 1.In this work,by constructing appropriate matrices γμ for the general covariant Dirac equation,we further extend the fermion tunnelling method to 5-dimensional static and rotating black lenses.As a result,it is interesting to find as in black hole cases,fermions tunnelling can also result in correct Hawking temperatures for the static and rotating black lenses.展开更多
文摘The effect of hydrostatic pressure on the vibration dispersion characteristics of fluid-shell coupled structures was studied.Both fluid-loaded cylindrical shells and fluid-filled cylindrical shells were considered.Numerical analysis was applied to solve the dispersion equations for shells filled with or loaded with fluid at various hydrostatic pressures.The results for external pressure showed that non-dimensional axial wave numbers are nearly independent when the pressure is below the critical level.The influence of internal pressure on wave numbers was found significant for the real branch s=1 and the complex branches of dispersion curves.The presence of internal pressure increased the cut on frequencies for the branch s=1 for high order wave modes.
基金supported by the Korea Research Foundation Grant funded by the Korean Government(MOEHRD),the MKE(The Ministry of Knowledge Economy,Korea)the ITRC(Information Technology Research Center)support program(NIPA-2009-(C1090-0902-0007))
文摘Vehicle detectition in still images is a comparatively difficult task. This paper presents a method for this task by using boosted local pattern detector constructed from two local features including Haar-like and oriented gradient features. The whole process is composed of three stages. In the first stage, local appearance features of vehicles and non-vehicle objects are extracted. Haar-tike and oriented gradient features are extracted separately in this stage as local features. In the second stage, Adabeost algorithm is used to select the most discriminative features as weak detectors from the two local feature sets, and a strong local pattern detector is built by the weighted combination of these selected weak detectors. Finally, vehicle detection can be performed in still images by using the boosted strong local feature detector. Experiment results show that the local pattern detector constructed in this way combines the advantages of Haar-like and oriented gradient features, and can achieve better detection results than the detector by using single Haar-like features.
基金Grants-in-Aid for Scientific Research from YOKOYAMA Foundation for Clinical Pharmacologya Grant-in-Aid from the Center of Excellence (COE) from the Ministry of Education, Culture, Sports, Science and Technology of JapanGrant-in-Aid from the Ministry of Education, Culture, Sports, Science and Technology of Japan No. 17590470
文摘AIM: To examine whether the sedative effects assessed by psychomotor tests would depend on the cytochrome P450 (CYP ) 2C19 genotypes after an infusion regimen of diazepam commonly used forgastrointestinal endoscopy in Japan. METHODS: Fifteen healthy Japanese volunteers consisting of three different CYP2C19 genotype groups underwent a critical ? icker fusion test, an eye movement analysis and a postural sway test as a test for physical sedative effects, and a visual analog scale (VAS) symptom assessment method as a test for mental sedative effects during the 336 h period after the intravenous infusion of diazepam (5 mg). RESULTS: The physical sedative effects assessed by the critical flicker test continued for 1 h (t values of 5 min, 30 min and 60 min later: 4.35, 5.00 and 3.19, respectively) and those by the moving radial area of a postural sway test continued for 3 h (t values of 5 h, 30 h, 60 min and 3 h later: -4.05, -3.42, -2.17 and -2.58, respectively), which changed significantly compared with the baseline level before infusion (P < 0.05). On the other hand, the mental sedative effects by the VAS method improved within 1 h. The CYP2C19 genotype-dependent differences in the postinfusion sedative effects were not observed in any of the four psychomotor function tests. CONCLUSION: With the psychomotor tests, the objective sedative effects of diazepam continued for 1 h to 3 h irrespective of CYP2C19 genotype status and the subjective sedative symptoms improved within 1 h. Up to 3 h of clinical care appears to be required after the infusion of diazepam, although patients feel subjectively improved.
基金Project supported by the Natural Science Foundation of China(No. 50378041) and the Specialized Research Fund for the Doc-toral Program of Higher Education (No. 20030487016), China
文摘A new structural damage identification method using limited test static displacement based on grey system theory is proposed in this paper. The grey relation coefficient of displacement curvature is defined and used to locate damage in the structure, and an iterative estimation scheme for solving nonlinear optimization programming problems based on the quadratic programming technique is used to identify the damage magnitude. A numerical example of a cantilever beam with single or multiple damages is used to examine the capability of the proposed grey-theory-based method to localize and identify damages. The factors of meas-urement noise and incomplete test data are also discussed. The numerical results showed that the damage in the structure can be localized correctly through using the grey-related coefficient of displacement curvature, and the damage magnitude can be iden-tified with a high degree of accuracy, regardless of the number of measured displacement nodes. This proposed method only requires limited static test data, which is easily available in practice, and has wide applications in structural damage detection.
文摘Objective. To evaluate the diagnostic criteria for the localization of acquired arteriovenous fistulas (AVFs) by color Doppler flow imaging (CDFI) based on the features of their hemodynamic changes. Methods. The shape and hemodynamic changes of involved vessels which could be helpful to localize the sites of fistulas were studied according to the observation of 10 cases of acquired AVFs. Results. The sites of the fistulas could be shown by two dimensional ultrasonography and color flow imaging in 40%and 80%cases, respectively. In all cases, turbulent high velocity flow was present at the sites of the fistulas, low resistant flow was present in the arteries proximal to the fistulas, and artery like flow was detected in the veins. Conclusion. CDFI was accurate for the localization of acquired AVFs, which were mainly localized by their hemodynamic changes shown by pulse Doppler ultrasound.
文摘AIM:To review percutaneous transhepatic portal venoplasty and stenting(PTPVS)for portal vein anastomotic stenosis(PVAS)after liver transplantation (LT). METHODS:From April 2004 to June 2008,16 of 18 consecutive patients(11 male and 5 female;aged 17-66 years,mean age 40.4 years)underwent PTPVS for PVAS.PVAS occurred 2-10 mo after LT(mean 5.0 mo). Three asymptomatic patients were detected on routine screening color Doppler ultrasonography(CDUS). Fifteen patients who also had typical clinical signs of portal hypertension(PHT)were identified by contrastenhanced computerized tomography(CT)or magnetic resonance imaging.All procedures were performed under local anesthesia.If there was a PVAS<75%, the portal pressure was measured.Portal venoplasty was performed with an undersized balloon and slowly inflated.All stents were deployed immediately following the predilation.Follow-ups,including clinical course, stenosis recurrence and stent patency which were evaluated by CDUS and CT,were performed. RESULTS:Technical success was achieved in all patients.No procedure-related complications occurred. Liver function was normalized gradually and the symptoms of PHT also improved following PTPVS.In 2 of 3 asymptomatic patients,portal venoplasty and stenting were not performed because of pressure gradients<5 mmHg.They were observed with periodic CDUS or CT.PTPVS was performed in 16 patients.In 2 patients,the mean pressure gradients decreased from 15.5 mmHg to 3.0 mmHg.In the remaining 14 patients,a pressure gradient was not obtained because of>75%stenosis and typical clinical signs of PHT.In a 51-year-old woman,who suffered from massive ascites and severe bilateral lower limb edema after secondary LT,PVAS complicated hepatic vein stenosis and inferior vena cava(IVC)stenosis. Before PTPVS,a self-expandable and a balloonexpandable metallic stent were deployed in the IVC and right hepatic vein respectively.The ascites and edema resolved gradually after treatment.The portosystemic collateral vessels resulting from PHT were visualized in 14 patients.Gastroesophageal varices became invisible on poststenting portography in 9 patients.In a 28-yearold man with hepatic encephalopathy,a pre-existing meso-caval shunt was detected due to visualization of IVC on portography.After stenting,contrast agents flowed mainly into IVC via the shunt and little flowed into the portal vein.A covered stent was deployed into the superior mesenteric vein to occlude the shunt. Portal hepatopetal flow was restored and the IVC became invisible.The patient recovered from hepatic encephalopathy.A balloon-expandable Palmaz stent was deployed into hepatic artery for anastomotic stenosis before PTPVS.Percutaneous transhepatic internal-external biliary drainage was performed in 2 patients with obstructive jaundice.Portal venous patency was maintained for 3.3-56.6 mo(mean 33.0 mo) and all patients remained asymptomatic.CONCLUSION:With technical refinements,early detection and prompt treatment of complications,and advances in immunotherapy,excellent results can be achieved in LT.
基金Supported by the National Natural Science Foundation of China under Grant No. 10573004
文摘Using the third-order WKB approximation, we evaluate the quasinormal frequencies of massless Dirac field perturbation around a Reissner Nordstrom black hole surrounded by a static and spherically symmetric quintessence. We study the variation of quasinormal frequencies with the quintessential state parameter ε, the total angular momentum number |k|, the charge Q, and the overtone number n changes, respectively. Moreover, from the results we obtained, we find that the massless Dirac field damps more slowly due to the presence of quintessence.
文摘Increasing reports on application and safety of liposomal amphotericin B (Amphotec) in the treatment of deep fungal infections have been described recently. This is the first report that a case of liver abscess due to Candida albicans was completely cured with intra-abscess and intravenous administration of liposomal amphotericin B without recurrence in three-year follow-up period.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10905015 and 10747122the Foundation of Anhui Educational Committee under Grant No. 2009SQRZ010
文摘By using the quantum magnetohydrodynamic model, the electrostatic waves in weakly magnetized quantum plasmas are investigated. The electrons are treated as a quantum and magnetized species, while the ions are classical unmagnetized ones. The general dispersion relations are derived. It is shown that, both the high frequency electron waves (Langmuire wave and upper-hybrid wave) and the low frequency ion acoustic wave can propagate when the plasmas are cold.
基金supported by the Scientific Research Foundation of the Education Department of Liaoning Province,China (Grant No.L2011195)
文摘Black lenses with L(n,1) horizon topology in five dimensions have many unusual properties shared by neither Myers-Perry black holes with event-horizon topology S 3,nor 5-dimensional black rings with event-horizon topology S 2 × S 1.In this work,by constructing appropriate matrices γμ for the general covariant Dirac equation,we further extend the fermion tunnelling method to 5-dimensional static and rotating black lenses.As a result,it is interesting to find as in black hole cases,fermions tunnelling can also result in correct Hawking temperatures for the static and rotating black lenses.