In the last few years, transcatheter aortic valve implantation (TAVI) has become an alternative procedure in patients with severe aortic stenosis and high risk for surgical aortic replacement. Due to the anatomic co...In the last few years, transcatheter aortic valve implantation (TAVI) has become an alternative procedure in patients with severe aortic stenosis and high risk for surgical aortic replacement. Due to the anatomic correlation between aortic valve structure and conduction system of the heart, one of the most common complications after TAVI is conduction system disturbances which including bundle branch block, complete heart block and need for permanent pacemaker implantation. Although these disturbances are usually not lethal, they may have a great influence on patients' state and long term-survival. Several risk factors for conduction disturbances have been identified which including age, anatomy of the heart, periprocedural factors, type of implanted valve, preexisting abnormalities and comorbidities. As this technique becomes more familiar to physicians, patients should be carefully screened for risk factors for the development of conduction abnormalities after TAVI in order to provide effective prevention and proper treatment.展开更多
Background Aortic valve stenosis (AS) is very common in the elderly patients above 80 years. Transcatheter aortic valve replacement (TAVR) in such patients is being increasingly performed. This study sought to ass...Background Aortic valve stenosis (AS) is very common in the elderly patients above 80 years. Transcatheter aortic valve replacement (TAVR) in such patients is being increasingly performed. This study sought to assess in-hospital outcome differences between octogenarians and nonagenarians and predictors of mortality in nonagenarians undergoing TAVR with severe AS. Method The study population was derived from the National Inpatient Sample (MS) for the years 2012-2014 using ICD-9 CM procedure codes 35.05 and 35.06 for TAVR. Hospitalizations below 80 years of age were excluded. After performing propensity score matching (1: 2), in-hospital outcomes were compared in matched cohorts. Then, multivariate model was developed to analyze predictors of in-hospital mortality in nonagenarians. Results There were 11,630 hospitalizations in the octogenarian and 5815 hospitalizations in the nonagenarian group. Primary outcome of in-hospital mortality (6% vs. 4.1%, P ≤ 0.001) was higher in nonagenarians compared to octogenarians. Secondary outcomes including stroke (3.4% vs. 2.8%, P ≤ 0.001), renal failure (18.9% vs. 17.3%, P ≤0.001), blood transfusion (35% vs. 32.6%, P ≤ 0.001), vascular complications (4.5% vs. 3.5%, P ≤ 0.001), and pacemaker implantation (27.8% vs. 24.8%, P ≤ 0.001) were higher in nonagenarians. There was no difference in their length of stay. Median cost (70,3745 vs. 65,3815, P ≤ 0.001) was slightly higher with nonagenarian. Conclusions Although in-hospital mortality is slightly higher in nonagenarians, it is acceptable. This difference in mortality is at least partly explained by higher complications in nonagenarians. Efforts should be made to decrease the complications which can further narrow the difference in in-hospital mortality between the groups.展开更多
Conversion of methane by steam reforming was carried out by means of dielectric-barrier discharge.A systemic procedure was employed to determine the suitable experimental conditions.It was found that one of the plasma...Conversion of methane by steam reforming was carried out by means of dielectric-barrier discharge.A systemic procedure was employed to determine the suitable experimental conditions.It was found that one of the plasma generators can match the system best.A higher power input can always bring a higher conversion,but the selectivity to C2H6 decreased from 52.48% to 39.43% as the power increased from 20W to 49W.When discharge distance was 4mm,selectivities to almost all main products reached the max.The inner electrode made of stainless steel and the outer electrode with aluminum foil were one of the best options which can obviously enhance the conversion of methane.A larger flow rate always resulted in a lower conversion of methane.In the most time,19.93% steam promoted conversion of methane.展开更多
A device to activate lignite and sludge by electro-hydraulic impulse is presented. It comprises an impulse current generator constituted by a high voltage transformer, a high voltage silicon rectifier, a current-limit...A device to activate lignite and sludge by electro-hydraulic impulse is presented. It comprises an impulse current generator constituted by a high voltage transformer, a high voltage silicon rectifier, a current-limiting resistor, a capacitor bank and an air-break switch, and a lignite and sludge appliance made up of two plane electrodes and a working chamber. The installation activates the lignite or sludge delivered to the working chamber by the impulse current that is from the generator to puncture the main gap in the working chamber, raise the temperature therein up to (20 000 to 40 000) K and the energy density to as high as 109 Jm-3, and form a plasma piston. The alternative development and attenuation of plasma expansion makes the lignite in a number of physical and chemical processes resulting in diverse active radicals and ions, and also breaks it into grains mostly smaller than 250 mm. It is founded by experimental study that the technology can raise the content of nitro-nitrogen by 1.4 to 1.5 times and that of dissoluble organic substances by 5 to 10 times which is probably attributed to the decomposition of the ample germs in the lignite. The calculated power requirement to activate lignite is about (50 to 60) kWht-1. In comparison with muck applied to cucumber cultivation, the activated lignite demonstrates its features as an effective and economical green fertilizer by the same yield with half amount. These findings imply a promising access to green fertilizer.展开更多
Objective To evaluate the monitoring and diagnostic potential of MR in fetal lung development using lung signal intensity changes in the fetus. Methods The lung-to-liver intensity ratio was calculated by means of regi...Objective To evaluate the monitoring and diagnostic potential of MR in fetal lung development using lung signal intensity changes in the fetus. Methods The lung-to-liver intensity ratio was calculated by means of region-of-interest analysis in all 35 fetuses including 7 bilateral urinary anomalies, 9 unilateral urinary anomalies, 5 pulmonary anomalies, and 14 others. Results All fetuses with urinary anomalies and pulmonary anomalies showed low ratio of lung-to-liver signal intensity. Conclusion Low ratio of lung-to-liver signal intensity on MR imaging indicates pulmonary hypoplasia after 22 weeks’ gestation.展开更多
As the operation time of heat exchanger is increased, the thermal performance of them is gradually degraded due to fouling generated by water-borne deposits which are known to reduce the thermal efficiencies. Currentl...As the operation time of heat exchanger is increased, the thermal performance of them is gradually degraded due to fouling generated by water-borne deposits which are known to reduce the thermal efficiencies. Currently, thermal performance management of heat exchangers is more importantly issued for long term operation. Therefore, the performance evaluation techniques are required to improve the present method for the integrity evaluation of heat exchangers because of the exclusion of fouling calculation and the uncertainty analysis. This paper describes the developed thermal performance evaluation technique applied to the safety-related heat exchangers such as component cooling heat exchangers in a nuclear power plants.展开更多
We previously identified a subcortical maternal complex (SCMC) that is essential for early embryogenesis and female fertility in mice. However, the molecular mechanism by which the SCMC affects female fertility rema...We previously identified a subcortical maternal complex (SCMC) that is essential for early embryogenesis and female fertility in mice. However, the molecular mechanism by which the SCMC affects female fertility remains largely uncharacterized. Here, we report that a novel maternal protein, zinc finger BED-type containing 3 (Zbed3), participates in the SCMC. Depletion of maternal Zbed3 results in reduced fecundity of females, because of the impaired and delayed development in a proportion of mutant embryos. The loss of maternal Zbed3 results in asymmetric zygotic division and abnormal distributions of organeUes in the affected oocytes and zygotes, similar to the phenotypes observed in females with disrupted core SCMC genes. Further investiga- tion revealed that these phenotypes are associated with disrupted dynamics of microtubules and/or formation of cytoplasmic lat- tices (CPLs). The stability and localization of Zbed3 depend on, but are not required for, the formation of the SCMC. Thus, our data suggest Zbed3 as one of downstream proteins mediating SCMC functions and provide further insights into the roles of the SCMC and CPLs in female fertility.展开更多
Blue top-emitting organic light-emitting devices (TEOLEDs) are demonstrated by employing Alq3 as phase shift adjustment layer (PSAL) to increase the phase shift on reflection of the top electrode within a range, w...Blue top-emitting organic light-emitting devices (TEOLEDs) are demonstrated by employing Alq3 as phase shift adjustment layer (PSAL) to increase the phase shift on reflection of the top electrode within a range, which also improves the light out-coupling. By adjusting the thickness of P SAL, the CIEx,y of devices, which utilize 2, 7-Di-pyrenyl-9, 9-spiro-bifluorene (DPSF) as emitting layer, changes from (0.16, 0.50) to (0.18, 0.37). The maximnum current efficiency of 7.1 cd/A is acquired under 4.5 V with an increasing luminance of 139 cd/m^2. Compared with adjusting the total thickness of organic layer, it is more beneficial for achieving blue TEOLEDs with high efficiency.展开更多
In this article,the random walking method is used to solve the steady linear convection-diffusion equation(CDE)with disc boundary condition.The integral solution corresponding to the random walking method is deduced a...In this article,the random walking method is used to solve the steady linear convection-diffusion equation(CDE)with disc boundary condition.The integral solution corresponding to the random walking method is deduced and the relationship between the diffusion coefficient of CDE and the intensity of the random diffusion motion is obtained.The random number generator for arbitrary axisymmetric disc boundary is deduced through the polynomial fitting and inverse transform sampling method.The proposed method is tested through two numerical cases.The results show that the random walking method can solve the steady linear CDE effectively.The influence of the parameters on the results is also studied.It is found that the error of the solution can be decreased by increasing the particle releasing rate and the total walking time.展开更多
文摘In the last few years, transcatheter aortic valve implantation (TAVI) has become an alternative procedure in patients with severe aortic stenosis and high risk for surgical aortic replacement. Due to the anatomic correlation between aortic valve structure and conduction system of the heart, one of the most common complications after TAVI is conduction system disturbances which including bundle branch block, complete heart block and need for permanent pacemaker implantation. Although these disturbances are usually not lethal, they may have a great influence on patients' state and long term-survival. Several risk factors for conduction disturbances have been identified which including age, anatomy of the heart, periprocedural factors, type of implanted valve, preexisting abnormalities and comorbidities. As this technique becomes more familiar to physicians, patients should be carefully screened for risk factors for the development of conduction abnormalities after TAVI in order to provide effective prevention and proper treatment.
文摘Background Aortic valve stenosis (AS) is very common in the elderly patients above 80 years. Transcatheter aortic valve replacement (TAVR) in such patients is being increasingly performed. This study sought to assess in-hospital outcome differences between octogenarians and nonagenarians and predictors of mortality in nonagenarians undergoing TAVR with severe AS. Method The study population was derived from the National Inpatient Sample (MS) for the years 2012-2014 using ICD-9 CM procedure codes 35.05 and 35.06 for TAVR. Hospitalizations below 80 years of age were excluded. After performing propensity score matching (1: 2), in-hospital outcomes were compared in matched cohorts. Then, multivariate model was developed to analyze predictors of in-hospital mortality in nonagenarians. Results There were 11,630 hospitalizations in the octogenarian and 5815 hospitalizations in the nonagenarian group. Primary outcome of in-hospital mortality (6% vs. 4.1%, P ≤ 0.001) was higher in nonagenarians compared to octogenarians. Secondary outcomes including stroke (3.4% vs. 2.8%, P ≤ 0.001), renal failure (18.9% vs. 17.3%, P ≤0.001), blood transfusion (35% vs. 32.6%, P ≤ 0.001), vascular complications (4.5% vs. 3.5%, P ≤ 0.001), and pacemaker implantation (27.8% vs. 24.8%, P ≤ 0.001) were higher in nonagenarians. There was no difference in their length of stay. Median cost (70,3745 vs. 65,3815, P ≤ 0.001) was slightly higher with nonagenarian. Conclusions Although in-hospital mortality is slightly higher in nonagenarians, it is acceptable. This difference in mortality is at least partly explained by higher complications in nonagenarians. Efforts should be made to decrease the complications which can further narrow the difference in in-hospital mortality between the groups.
基金Supported by the National iqatural Science Foundation of China (20606023, 20490203).
文摘Conversion of methane by steam reforming was carried out by means of dielectric-barrier discharge.A systemic procedure was employed to determine the suitable experimental conditions.It was found that one of the plasma generators can match the system best.A higher power input can always bring a higher conversion,but the selectivity to C2H6 decreased from 52.48% to 39.43% as the power increased from 20W to 49W.When discharge distance was 4mm,selectivities to almost all main products reached the max.The inner electrode made of stainless steel and the outer electrode with aluminum foil were one of the best options which can obviously enhance the conversion of methane.A larger flow rate always resulted in a lower conversion of methane.In the most time,19.93% steam promoted conversion of methane.
基金the National Natural Science Foundation of China (59979029)
文摘A device to activate lignite and sludge by electro-hydraulic impulse is presented. It comprises an impulse current generator constituted by a high voltage transformer, a high voltage silicon rectifier, a current-limiting resistor, a capacitor bank and an air-break switch, and a lignite and sludge appliance made up of two plane electrodes and a working chamber. The installation activates the lignite or sludge delivered to the working chamber by the impulse current that is from the generator to puncture the main gap in the working chamber, raise the temperature therein up to (20 000 to 40 000) K and the energy density to as high as 109 Jm-3, and form a plasma piston. The alternative development and attenuation of plasma expansion makes the lignite in a number of physical and chemical processes resulting in diverse active radicals and ions, and also breaks it into grains mostly smaller than 250 mm. It is founded by experimental study that the technology can raise the content of nitro-nitrogen by 1.4 to 1.5 times and that of dissoluble organic substances by 5 to 10 times which is probably attributed to the decomposition of the ample germs in the lignite. The calculated power requirement to activate lignite is about (50 to 60) kWht-1. In comparison with muck applied to cucumber cultivation, the activated lignite demonstrates its features as an effective and economical green fertilizer by the same yield with half amount. These findings imply a promising access to green fertilizer.
文摘Objective To evaluate the monitoring and diagnostic potential of MR in fetal lung development using lung signal intensity changes in the fetus. Methods The lung-to-liver intensity ratio was calculated by means of region-of-interest analysis in all 35 fetuses including 7 bilateral urinary anomalies, 9 unilateral urinary anomalies, 5 pulmonary anomalies, and 14 others. Results All fetuses with urinary anomalies and pulmonary anomalies showed low ratio of lung-to-liver signal intensity. Conclusion Low ratio of lung-to-liver signal intensity on MR imaging indicates pulmonary hypoplasia after 22 weeks’ gestation.
文摘As the operation time of heat exchanger is increased, the thermal performance of them is gradually degraded due to fouling generated by water-borne deposits which are known to reduce the thermal efficiencies. Currently, thermal performance management of heat exchangers is more importantly issued for long term operation. Therefore, the performance evaluation techniques are required to improve the present method for the integrity evaluation of heat exchangers because of the exclusion of fouling calculation and the uncertainty analysis. This paper describes the developed thermal performance evaluation technique applied to the safety-related heat exchangers such as component cooling heat exchangers in a nuclear power plants.
文摘We previously identified a subcortical maternal complex (SCMC) that is essential for early embryogenesis and female fertility in mice. However, the molecular mechanism by which the SCMC affects female fertility remains largely uncharacterized. Here, we report that a novel maternal protein, zinc finger BED-type containing 3 (Zbed3), participates in the SCMC. Depletion of maternal Zbed3 results in reduced fecundity of females, because of the impaired and delayed development in a proportion of mutant embryos. The loss of maternal Zbed3 results in asymmetric zygotic division and abnormal distributions of organeUes in the affected oocytes and zygotes, similar to the phenotypes observed in females with disrupted core SCMC genes. Further investiga- tion revealed that these phenotypes are associated with disrupted dynamics of microtubules and/or formation of cytoplasmic lat- tices (CPLs). The stability and localization of Zbed3 depend on, but are not required for, the formation of the SCMC. Thus, our data suggest Zbed3 as one of downstream proteins mediating SCMC functions and provide further insights into the roles of the SCMC and CPLs in female fertility.
文摘Blue top-emitting organic light-emitting devices (TEOLEDs) are demonstrated by employing Alq3 as phase shift adjustment layer (PSAL) to increase the phase shift on reflection of the top electrode within a range, which also improves the light out-coupling. By adjusting the thickness of P SAL, the CIEx,y of devices, which utilize 2, 7-Di-pyrenyl-9, 9-spiro-bifluorene (DPSF) as emitting layer, changes from (0.16, 0.50) to (0.18, 0.37). The maximnum current efficiency of 7.1 cd/A is acquired under 4.5 V with an increasing luminance of 139 cd/m^2. Compared with adjusting the total thickness of organic layer, it is more beneficial for achieving blue TEOLEDs with high efficiency.
基金supported by the International Scientific and Technological Cooperation Program of China(Grant No.2011DFG13020)the China Postdoctoral Science Foundation(Grant No.2013M530043)the National Hi-Tech Research and Development Program of China("863"Project)(Grant No.2007AA05Z426)
文摘In this article,the random walking method is used to solve the steady linear convection-diffusion equation(CDE)with disc boundary condition.The integral solution corresponding to the random walking method is deduced and the relationship between the diffusion coefficient of CDE and the intensity of the random diffusion motion is obtained.The random number generator for arbitrary axisymmetric disc boundary is deduced through the polynomial fitting and inverse transform sampling method.The proposed method is tested through two numerical cases.The results show that the random walking method can solve the steady linear CDE effectively.The influence of the parameters on the results is also studied.It is found that the error of the solution can be decreased by increasing the particle releasing rate and the total walking time.