Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian Univers...Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning Province,China.展开更多
OBJECTIVE The emergence of evolving variants of Coronavirus disease 2019(COVID-19)has fostered the need for change of newer and adaptive treatments for these infections.During the COVID-19 pandemic and persists,tradit...OBJECTIVE The emergence of evolving variants of Coronavirus disease 2019(COVID-19)has fostered the need for change of newer and adaptive treatments for these infections.During the COVID-19 pandemic and persists,traditional Chinese medicine(TCM)herbs exhibit significant bioactivity and therapeutic effect.This study is aimed to evaluate the efficacy of four TCM preparations on 28-day mortality risk of patients and changes of the laboratory indicators.METHODS The retrospective cohort study included patients with COVID-19 who were admitted to the Jiangsu Province Hospital of Chinese Medicine from December 15,2022 to January 15,2023,and those died within 48 hours of admission or cannot be tracked for outcomes were excluded.The primary outcome was survival status in 28 days(death or survival)starting from the day of admission.The second outcomes were laboratory indicators,including absolute lymphocyte count,lactate dehydrogenase,creatinine,and blood urea nitrogen.Binary logistic regressions were used to estimate the effect of TCM preparations on the primary and secondary outcomes in main analysis.Meanwhile,heterogeneity and robustness of results from main analysis were assessed by subgroup analyses and multiple sensitivity analyses.RESULTS 1816 eligible patients were included in analysis dataset,including 573 patients received standard care(control group)and 1243 patients received TCM preparations(hospital preparation group).The 28-day mortality rate of hospital preparation group was lower than that of control group(4.75%vs.14.83%),and the difference was statistically significant(χ^(2)=54.666,P<0.001).The risk of 28-day mortality was 0.535 times lower in the hospital preparation group as compared with the control group(OR=0.46,95%CI:0.305-0.708,P<0.001)showed by multivariable binary logistic regressions.Subgroup analyses showed that taking TCM preparations reduced the 28-day mortality risk.Sensitivity analyses demonstrated that the results of the main analysis for primary outcomes were robust.For secondary outcomes,the risk of abnormal absolute lymphocyte counts at discharge in the hospital preparation group decreased by 0.284 times(OR=0.703,95%CI:0.515-0.961,P=0.027).CONCLUSION Compared with standard of care,taking four hospital preparations including Kanggan Heji,Feining Heji,Qishen Gubiao Keli,and Qianghuo Qushi Qingwen Heji decreased risk of 28-day mortality among hospitalized COVID-19 patients.TCM therapy achieves adequate therapeutic effects in COVID-19.展开更多
Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular st...Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular structure and luminescence properties,TADF molecules are far from meeting the needs of practical applications in terms of variety and number.In this paper,three twisted TADF molecules are studied and their photophysical properties are theoretically predicted based on the thermal vibrational correlation function method combined with multiscale calculations.The results show that all the molecules exhibit fast reverse intersystem crossing(RISC)rates(kRISC),predicting their TADF luminescence properties.In addition,the binding of DHPAzSi as the donor unit with different acceptors can change the dihedral angle between the ground and excited states,and the planarity of the acceptors is positively correlated with the reorganization energy,a property that has a strong influence on the non-radiative process.Furthermore,a decrease in the energy of the molecular charge transfer state and an increase in the kRISC were observed in the films.This study not only provides a reliable explanation for the observed experimental results,but also offers valuable insights that can guide the design of future TADF molecules.展开更多
Objective Comparative study on the feasibility,safety and outcome of transradial artery and transfemoral artery access for primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction(...Objective Comparative study on the feasibility,safety and outcome of transradial artery and transfemoral artery access for primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction(AMI).Methods Two hundred and eight patients with AMI episoded within 12 hours, male 159, female 49, age 58.9 ±11.9 (34～88)years, were randomly divided into transradial artery access for primary PCI (TRA pPCI) group of 106 cases and transfemoral artery access for PCI (TFA pPCI) group of 102 cases during Sept, 2000 to Aug, 2002. The protocols of the manipulation duration and the effect for TRA pPCI and TFA pPCI procedures were respectively compared, including the time of transradial artery puncture and the rate of puncture success at first time ; the time of guiding catheter engaging into target coronary ostium; the rate of patence in infarct related artery (IRA); total duration of manipulation and the successful rate.The incidence of complications such as bleeding, vessel injury,thrombi and embolism as well as the average stay of hospitalization between two groups was compared. The status and the incidance of vessel spasm were observed and the effect of medicine administration to prevent from and relieve the vascular spasm was evaluated. The time of Allen’s test before and after TRA pPCI , the inner diameter and the peak of blood velocity of the right and left radial artery were investigated with color Doppler vessel echography as well as the complications of radial artery were followed up 1 month after TRA pPCI procedure. Results Two cases in every TRA pPCI and TFA pPCI groups were crossed over each other because procedure of the transradial or transfemoral access was failure. One handred and six vessels (48 vessels in LAD,22 vessels in LCX and 36 vessels in RCA) associated with 28 vessels of total occlusion in TRA pPCI group and 102 vessels (51 vessels in LAD,18 veesles in LCX and 33 vessels in RCA) with 24 vessels in total occlusion in TFA pPCI group were angioplasticized . The successful rates of the first time puncture in access artery, the re patence IRA and pPCI were similar in TRA pPCI and TFA pPCI groups ( 93.4% vs 96.1% ;100% vs 100%; 96.2% vs 97.1% , P >0.05 ). There were no significant diffierence in the average time of puncture time of access artery ,engaging in target vessels of guiding catheters and the total procedure of PCI between the two groups ( 1.3 ±0.3s vs 1.2 ±0.3s ; 6.0 ±1.6min vs 5.8 ±0.9min ; 49.2 ±24.1min vs 46.5 ± 26.4min , P >0.05 ). The access artery complications such as bleeding ,hematoma and embolism as well the veneous thrombosis in TFA pPCI group were much more than those in TRA pPCI group(p< 0.01 ). Although slight artery spasm of 4.7% cases in TRA pPCI group was happened during the procedure of PCI , the procedure had being continued after administration of medicine to release the spasm. The time of Allen’s test ,diameter and the systolic velocity of blood in daul radial arteries were no significant change before and after pPCI.Conclusions The duration and effect by TRA pPCI for AMI with stable hemodynamics was similar to TFA pPCI. The complications such as of bleeding,vessel injury, thrombi and embolism by TRA pPCI were few, and it was unnecessary to discontinue the anticoagulation medicine. TRA pPCI might be selected as a access vessel for pPCI in AMI patients with stable hemodynamics.展开更多
More focuses of foreign language teaching theory and practice are on the study of first language and second language acquisition. The article deals with the concept of first and second language acquisition, the relati...More focuses of foreign language teaching theory and practice are on the study of first language and second language acquisition. The article deals with the concept of first and second language acquisition, the relationship between them and the factors influencing on them. The characteristics of the children acquisition and adult acquisition are also studied.展开更多
The micro-combustion chamber is the key component for micro-TPV systems. To improve the combustor wall temperature level and its uniformity and efficiency, an improved flat micro-combustor with a front cavity is built...The micro-combustion chamber is the key component for micro-TPV systems. To improve the combustor wall temperature level and its uniformity and efficiency, an improved flat micro-combustor with a front cavity is built, and the combustion performance of the original and improved combustors of premixed H2/air flames under various inlet velocities and equivalence ratios is numerically investigated. The effects of the front cavity height and length on the outer wall temperature and efficiency are also discussed. The front cavity significantly improves the average outer wall temperature, outer wall temperature uniformity, and combustion efficiency of the micro-combustor, increases the area of the high temperature zone, and enhances the heat transfer between the burned blends and inner walls. The micro-combustor with the front cavity length of 2.0 mm and height of 0.5 mm is suitable for micro-TPV system application due to the relatively high outer wall temperature, combustion efficiency, and the most uniform outer wall temperature.展开更多
A case study of seismic response of an earth embankment foundation on liquefiable soils in Kansai area,western Japan was presented. Based on a calibrated cyclic elasto-plastic constitutive model for liquefiable sand a...A case study of seismic response of an earth embankment foundation on liquefiable soils in Kansai area,western Japan was presented. Based on a calibrated cyclic elasto-plastic constitutive model for liquefiable sand and Biot dynamic coupled theory,the seismic analysis was carried out by using a dynamic effective stress finite element method under plane strain condition. A recent design study was illustrated in detail for a river earth embankment subjected to seismic excitation on the saturated deposits with liquefiable sands. Simulated results of the embankment foundation during liquefaction were obtained for acceleration,displacement,and excess pore water pressures,which were considered to yield useful results for earthquake geotechnical design. The results show that the foundation soil reaches a fully liquefied state with high excess pore pressure ratios approaching to 1.0 due to the earthquake shaking. At the end of the earthquake,the extensive liquefaction causes about 1.0 m lateral spreading at the toe and 60 cm settlement at the crest of the earth embankment.展开更多
Natural convection heat transfer from annular finned tubes was studied numerically. Effects of fin spacing, temperature difference and tube diameter on flow pathlines and local heat transfer were also studied. It was ...Natural convection heat transfer from annular finned tubes was studied numerically. Effects of fin spacing, temperature difference and tube diameter on flow pathlines and local heat transfer were also studied. It was shown that pathlines remain mostly circular for different geometries. Moreover, the contributions of fin periphery, fin side and bare tube to heat transfer were specified. It was shown that the heat transfer per unit area of fin periphery can be several times that of other parts. Moreover, in higher finspacing, the heat transfer from the bare tube can be more important than fin sides.展开更多
Kunming,a city in southwest China,has a climate that is different from most of the other places in the world because of its unique geographical characteristics.Due to its temperate climate,most of the residential buil...Kunming,a city in southwest China,has a climate that is different from most of the other places in the world because of its unique geographical characteristics.Due to its temperate climate,most of the residential buildings in this region are naturally ventilated.Accordingly,a winter thermal comfort study was conducted in Kunming to reveal the thermal response of residents.Indoor and outdoor environmental parameters were measured,and participants were investigated about their clothing,thermal sensations,thermal preferences,and thermal acceptance using online questionnaires.Data from 162 valid questionnaires were collected in the survey.Although the climate is referred to as“mild”,the survey showed that the indoor temperature during winter was lower than the typical comfort range.Nevertheless,the participants responded that most of them felt neutral and comfortable.The neutral temperature of participants living in Kunming was determined to be 16.96℃.The acceptable thermal sensation vote(TSV)range of the residents is-0.72 to 1.52.The acceptable indoor air temperature range is 15.03℃to 19.55℃,and the optimum indoor air temperature is 17.2℃.According to this study,the existing thermal comfort evaluation models can hardly predict residents’thermal responses in Kunming well.展开更多
A new meso-mechanical testing scheme based on SEM was developed to carry out the experiment of microfracturing process of rocks. The microfracturing process of the pre-crack marble sample on surrounding rock in the im...A new meso-mechanical testing scheme based on SEM was developed to carry out the experiment of microfracturing process of rocks. The microfracturing process of the pre-crack marble sample on surrounding rock in the immerged Long-big tunnel in Jinping Cascade II Hydropower Station under uniaxial compression was recorded by using the testing scheme. According to the stereology theory, the propagation and coalescent of cracks at meso-scale were quantitatively investigated with digital technology. Therefore, the basic geometric information of rock microcracks such as area, angle, length, width, perimeter, was obtained from binary images after segmentation. The failure mechanism of specimen under uniaxial compression with the quantitative information was studied from macro and microscopic point of view. The results show that the image of microfracturing process of the specimen can be observed and recorded digitally. During the damage of the specimen, the distribution of microcracks in the specimen is still subjected to exponential distribution with some microcracks concentrated in certain regions. Finally, the change law of the fractal dimension of the local element in marble sample under different external load conditions is obtained by means of the statistical calculation of the fractal dimension.展开更多
A kind of complex additive mainly containing Al, Mg, F, and O was prepared. The synthetical performances of the property-modified prebaked anodes containing additives were tested in laboratory. On the basis of ideal t...A kind of complex additive mainly containing Al, Mg, F, and O was prepared. The synthetical performances of the property-modified prebaked anodes containing additives were tested in laboratory. On the basis of ideal testing results obtained, a large number of industrial prebaked property-modified anodes are prepared in a large-scale aluminum company. Further more, they are all used in 160 kA prebaked anode aluminum electrolysis cells. The statistic result show that, compared with common anodes, the property-modified ones enhance current by 11.6 kg per ton aluminum averagely.展开更多
High-temperature Ni-based alloys are widely used in the aerospace field due to their excellent properties,but the shortcomings of brittle fracture at the grain boundaries and poor plasticity at room temperature also l...High-temperature Ni-based alloys are widely used in the aerospace field due to their excellent properties,but the shortcomings of brittle fracture at the grain boundaries and poor plasticity at room temperature also limit their development to a certain extent.Researchers found that there areγ′precipitation phases similar to Ni_(3)Al in Pt-Al based alloys.In this paper,the CASTEP code of Materials Studio software package is used to simulate the thermal and mechanical properties ofγ′-Pt_(3)Al phase andγ′-Ni_(3)Al phase.By comparing the performance characteristics of the electronic structure,mechanical properties and point defect structure of the two,it is found that the stability,elastic deformation resistance and high temperature creep resistance of theγ′-Pt_(3)Al phase are better than those of theγ′-Ni_(3)Al phase.This will provide theoretical guidance for promoting the development of Pt-Al-based high-temperature materials.展开更多
Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on com...Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE＇s theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE＇s theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design.展开更多
There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that ma...There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that made by belt press.With the on-going improvement in technology,know-how & accumulated experiences, perhaps it’ s time for us to review the qualities & performances of synthetic diamond made by the cubic press more objectively.Studies were carried out on the performances of the two kinds of diamond by choosing from top brands & top qualities,with coarser mesh sizes 20/30 & 30/40.Comparisons were made on parameters, such as TI,TTI,PPC,bulk density,compact,roughness and arealight.And the diamonds chosen were used to produce the relevant diamond core drill bits and saw blades,their respective cutting performances such as cutting efficiency,segments consumption were measured and reported in this paper.The report demonstrates that producing the high quality diamond does not depend on the type of presses(Belt or Cubic) but rather on the know-how,technology and what it is made.展开更多
Ⅰ. Introduction Over the past two decades, microwave remote sensing has evolved into a focal point in the remote sensing area. This is due to the fact that in microwave band, we can acquire physical parameters about ...Ⅰ. Introduction Over the past two decades, microwave remote sensing has evolved into a focal point in the remote sensing area. This is due to the fact that in microwave band, we can acquire physical parameters about ocean, terrain and atmosphere on all weather condition. Research and application work about the aerial passive micro wave remote sensors has been done at Changchun Institute of Geography since 1973, under the unitary planning of Academia Sinica. Microwave radiometers of six freqency bands have been developed. Numerous remote sensing experiments were carried out, and large amount of scientific data were accumulated. Recently, theoretical models have展开更多
"Digital Earth"is one of integrated scientific technology based on development of information technology and modern space telemetry,and it possesses some special features such as application of great amount ..."Digital Earth"is one of integrated scientific technology based on development of information technology and modern space telemetry,and it possesses some special features such as application of great amount of geography data,which can describe the Earth in three dimensions and with higher resolution,i.e."virtual earth":the ordinary user also can readily obtain some information through certain means.Visualization and virtual reality are one展开更多
Background Traffic accidents,anti-terrorism,gas and chemical dangerous goods explosions,earthquake shock wave damage,and falling impacts in daily life and other events involving impact loads cause great harm to human ...Background Traffic accidents,anti-terrorism,gas and chemical dangerous goods explosions,earthquake shock wave damage,and falling impacts in daily life and other events involving impact loads cause great harm to human organs and tissues,and even life-threatening.Such injuries are called impact damage.Although during the previous wars,the treatment of impact injuries has been greatly improved,and its treatment has been widely used in clinical practice.However,under the current development of society,the impact damage incident has not only been limited to the battlefield.Extreme organizations,frequent industrial production accidents,aircraft trains and other accidents have extended the impact damage incidents into daily society,seriously jeopardizing the health of civilians.Therefore,in order to better treat the injured organs under the impact load,such as the reconstruction and recovery of organ tissues,it is necessary to establish a corresponding system of clinical treatment methods for impact damage.In vitro models of traumatic injury are helping elucidate the pathobiological mechanisms responsible for dysfunction and delayed cell functional variation after mechanical stimulation of the single waveform pressure.It is likely that injury outcome is related to the biomechanical parameters of the traumatic event such as amplitudes and durations.However,the influence of impulsive pressure on endothelial function has not yet been fully studied in vitro.In this study,we developed a pressure loading device that produced positive by modifying an in vitro fluid percussion model and examined the effects of the pressures on macrophages’basic functions.Methods To model variations in the biomechanical injury parameters and simplify the experiment,single-use syringe was chosen to be the cell container and a drop hammer driven fluid percussion injury system(FPI)was designed and built to generate a single waveform with adjustable peak pressure and durations.Mice macrophage cells(Raw 264.7)were subjected to three types of the single positive pressure(120 kPa,550 kPa and 1 100 kPa).Every 12 hours we detected its basic functions(including phagocytosis and proliferative capacity)during the following 48 hours,also the immediate cell death.Results This single waveform pressure loading device could produce positive pressure with amplitudes of 70~1 200 kPa.After the pressure loading,there is no significant differences between the control cells and experiment cells.However,it does have a notable effect on its basic functions.The results showed that its phagocytosis and proliferative capacity were getting increased with a peak value on36 h and suddenly decreasing on 48 h.Moreover,these 4 regular curves are in proportion to the pressure.And the experimental results also indicate that the cell impact platform can achieve a single impact loading on the cells.The impact mainly causes the functional changes of RAW264.7 cells instead of directly causing its death.The cell proliferation activity and phagocytosis function are enhanced to some extent.Conclusions Those results indicate that single waveform pressure have a main effect on cell’s biological functions,not on cell death.And these effects on functions did have a regular functional rela-tionship.To explore more regular curves and the mechanism,we need more experiments such as genomics technical.展开更多
文摘Hanyu Xu 1,Xuedan Song 1,*,Qing Zhang 1,Chang Yu 1,Jieshan Qiu 1,2,*1 Liaoning Key Lab for Energy Materials and Chemical Engineering,State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning Province,China.
文摘OBJECTIVE The emergence of evolving variants of Coronavirus disease 2019(COVID-19)has fostered the need for change of newer and adaptive treatments for these infections.During the COVID-19 pandemic and persists,traditional Chinese medicine(TCM)herbs exhibit significant bioactivity and therapeutic effect.This study is aimed to evaluate the efficacy of four TCM preparations on 28-day mortality risk of patients and changes of the laboratory indicators.METHODS The retrospective cohort study included patients with COVID-19 who were admitted to the Jiangsu Province Hospital of Chinese Medicine from December 15,2022 to January 15,2023,and those died within 48 hours of admission or cannot be tracked for outcomes were excluded.The primary outcome was survival status in 28 days(death or survival)starting from the day of admission.The second outcomes were laboratory indicators,including absolute lymphocyte count,lactate dehydrogenase,creatinine,and blood urea nitrogen.Binary logistic regressions were used to estimate the effect of TCM preparations on the primary and secondary outcomes in main analysis.Meanwhile,heterogeneity and robustness of results from main analysis were assessed by subgroup analyses and multiple sensitivity analyses.RESULTS 1816 eligible patients were included in analysis dataset,including 573 patients received standard care(control group)and 1243 patients received TCM preparations(hospital preparation group).The 28-day mortality rate of hospital preparation group was lower than that of control group(4.75%vs.14.83%),and the difference was statistically significant(χ^(2)=54.666,P<0.001).The risk of 28-day mortality was 0.535 times lower in the hospital preparation group as compared with the control group(OR=0.46,95%CI:0.305-0.708,P<0.001)showed by multivariable binary logistic regressions.Subgroup analyses showed that taking TCM preparations reduced the 28-day mortality risk.Sensitivity analyses demonstrated that the results of the main analysis for primary outcomes were robust.For secondary outcomes,the risk of abnormal absolute lymphocyte counts at discharge in the hospital preparation group decreased by 0.284 times(OR=0.703,95%CI:0.515-0.961,P=0.027).CONCLUSION Compared with standard of care,taking four hospital preparations including Kanggan Heji,Feining Heji,Qishen Gubiao Keli,and Qianghuo Qushi Qingwen Heji decreased risk of 28-day mortality among hospitalized COVID-19 patients.TCM therapy achieves adequate therapeutic effects in COVID-19.
文摘Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular structure and luminescence properties,TADF molecules are far from meeting the needs of practical applications in terms of variety and number.In this paper,three twisted TADF molecules are studied and their photophysical properties are theoretically predicted based on the thermal vibrational correlation function method combined with multiscale calculations.The results show that all the molecules exhibit fast reverse intersystem crossing(RISC)rates(kRISC),predicting their TADF luminescence properties.In addition,the binding of DHPAzSi as the donor unit with different acceptors can change the dihedral angle between the ground and excited states,and the planarity of the acceptors is positively correlated with the reorganization energy,a property that has a strong influence on the non-radiative process.Furthermore,a decrease in the energy of the molecular charge transfer state and an increase in the kRISC were observed in the films.This study not only provides a reliable explanation for the observed experimental results,but also offers valuable insights that can guide the design of future TADF molecules.
文摘Objective Comparative study on the feasibility,safety and outcome of transradial artery and transfemoral artery access for primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction(AMI).Methods Two hundred and eight patients with AMI episoded within 12 hours, male 159, female 49, age 58.9 ±11.9 (34～88)years, were randomly divided into transradial artery access for primary PCI (TRA pPCI) group of 106 cases and transfemoral artery access for PCI (TFA pPCI) group of 102 cases during Sept, 2000 to Aug, 2002. The protocols of the manipulation duration and the effect for TRA pPCI and TFA pPCI procedures were respectively compared, including the time of transradial artery puncture and the rate of puncture success at first time ; the time of guiding catheter engaging into target coronary ostium; the rate of patence in infarct related artery (IRA); total duration of manipulation and the successful rate.The incidence of complications such as bleeding, vessel injury,thrombi and embolism as well as the average stay of hospitalization between two groups was compared. The status and the incidance of vessel spasm were observed and the effect of medicine administration to prevent from and relieve the vascular spasm was evaluated. The time of Allen’s test before and after TRA pPCI , the inner diameter and the peak of blood velocity of the right and left radial artery were investigated with color Doppler vessel echography as well as the complications of radial artery were followed up 1 month after TRA pPCI procedure. Results Two cases in every TRA pPCI and TFA pPCI groups were crossed over each other because procedure of the transradial or transfemoral access was failure. One handred and six vessels (48 vessels in LAD,22 vessels in LCX and 36 vessels in RCA) associated with 28 vessels of total occlusion in TRA pPCI group and 102 vessels (51 vessels in LAD,18 veesles in LCX and 33 vessels in RCA) with 24 vessels in total occlusion in TFA pPCI group were angioplasticized . The successful rates of the first time puncture in access artery, the re patence IRA and pPCI were similar in TRA pPCI and TFA pPCI groups ( 93.4% vs 96.1% ;100% vs 100%; 96.2% vs 97.1% , P >0.05 ). There were no significant diffierence in the average time of puncture time of access artery ,engaging in target vessels of guiding catheters and the total procedure of PCI between the two groups ( 1.3 ±0.3s vs 1.2 ±0.3s ; 6.0 ±1.6min vs 5.8 ±0.9min ; 49.2 ±24.1min vs 46.5 ± 26.4min , P >0.05 ). The access artery complications such as bleeding ,hematoma and embolism as well the veneous thrombosis in TFA pPCI group were much more than those in TRA pPCI group(p< 0.01 ). Although slight artery spasm of 4.7% cases in TRA pPCI group was happened during the procedure of PCI , the procedure had being continued after administration of medicine to release the spasm. The time of Allen’s test ,diameter and the systolic velocity of blood in daul radial arteries were no significant change before and after pPCI.Conclusions The duration and effect by TRA pPCI for AMI with stable hemodynamics was similar to TFA pPCI. The complications such as of bleeding,vessel injury, thrombi and embolism by TRA pPCI were few, and it was unnecessary to discontinue the anticoagulation medicine. TRA pPCI might be selected as a access vessel for pPCI in AMI patients with stable hemodynamics.
文摘More focuses of foreign language teaching theory and practice are on the study of first language and second language acquisition. The article deals with the concept of first and second language acquisition, the relationship between them and the factors influencing on them. The characteristics of the children acquisition and adult acquisition are also studied.
基金Project(11802336) supported by the National Natural Science Foundation of China
文摘The micro-combustion chamber is the key component for micro-TPV systems. To improve the combustor wall temperature level and its uniformity and efficiency, an improved flat micro-combustor with a front cavity is built, and the combustion performance of the original and improved combustors of premixed H2/air flames under various inlet velocities and equivalence ratios is numerically investigated. The effects of the front cavity height and length on the outer wall temperature and efficiency are also discussed. The front cavity significantly improves the average outer wall temperature, outer wall temperature uniformity, and combustion efficiency of the micro-combustor, increases the area of the high temperature zone, and enhances the heat transfer between the burned blends and inner walls. The micro-combustor with the front cavity length of 2.0 mm and height of 0.5 mm is suitable for micro-TPV system application due to the relatively high outer wall temperature, combustion efficiency, and the most uniform outer wall temperature.
基金Projects (40802070, 40841014) supported by the National Natural Science Foundation of ChinaProject (B308) supported by Shanghai Leading Academic Discipline Project, China
文摘A case study of seismic response of an earth embankment foundation on liquefiable soils in Kansai area,western Japan was presented. Based on a calibrated cyclic elasto-plastic constitutive model for liquefiable sand and Biot dynamic coupled theory,the seismic analysis was carried out by using a dynamic effective stress finite element method under plane strain condition. A recent design study was illustrated in detail for a river earth embankment subjected to seismic excitation on the saturated deposits with liquefiable sands. Simulated results of the embankment foundation during liquefaction were obtained for acceleration,displacement,and excess pore water pressures,which were considered to yield useful results for earthquake geotechnical design. The results show that the foundation soil reaches a fully liquefied state with high excess pore pressure ratios approaching to 1.0 due to the earthquake shaking. At the end of the earthquake,the extensive liquefaction causes about 1.0 m lateral spreading at the toe and 60 cm settlement at the crest of the earth embankment.
文摘Natural convection heat transfer from annular finned tubes was studied numerically. Effects of fin spacing, temperature difference and tube diameter on flow pathlines and local heat transfer were also studied. It was shown that pathlines remain mostly circular for different geometries. Moreover, the contributions of fin periphery, fin side and bare tube to heat transfer were specified. It was shown that the heat transfer per unit area of fin periphery can be several times that of other parts. Moreover, in higher finspacing, the heat transfer from the bare tube can be more important than fin sides.
基金Project(2018YFC0704500)supported by the National Key R&D Program of ChinaProjects(51838007,52130803)supported by the National Natural Science Foundation of China。
文摘Kunming,a city in southwest China,has a climate that is different from most of the other places in the world because of its unique geographical characteristics.Due to its temperate climate,most of the residential buildings in this region are naturally ventilated.Accordingly,a winter thermal comfort study was conducted in Kunming to reveal the thermal response of residents.Indoor and outdoor environmental parameters were measured,and participants were investigated about their clothing,thermal sensations,thermal preferences,and thermal acceptance using online questionnaires.Data from 162 valid questionnaires were collected in the survey.Although the climate is referred to as“mild”,the survey showed that the indoor temperature during winter was lower than the typical comfort range.Nevertheless,the participants responded that most of them felt neutral and comfortable.The neutral temperature of participants living in Kunming was determined to be 16.96℃.The acceptable thermal sensation vote(TSV)range of the residents is-0.72 to 1.52.The acceptable indoor air temperature range is 15.03℃to 19.55℃,and the optimum indoor air temperature is 17.2℃.According to this study,the existing thermal comfort evaluation models can hardly predict residents’thermal responses in Kunming well.
基金Projects(50674040, 50539090) supported by the National Natural Science Foundation of ChinaProject(CX07B_128z) supported by the Cultivate Creative Postgraduate Foundation of Jiangsu Province, China
文摘A new meso-mechanical testing scheme based on SEM was developed to carry out the experiment of microfracturing process of rocks. The microfracturing process of the pre-crack marble sample on surrounding rock in the immerged Long-big tunnel in Jinping Cascade II Hydropower Station under uniaxial compression was recorded by using the testing scheme. According to the stereology theory, the propagation and coalescent of cracks at meso-scale were quantitatively investigated with digital technology. Therefore, the basic geometric information of rock microcracks such as area, angle, length, width, perimeter, was obtained from binary images after segmentation. The failure mechanism of specimen under uniaxial compression with the quantitative information was studied from macro and microscopic point of view. The results show that the image of microfracturing process of the specimen can be observed and recorded digitally. During the damage of the specimen, the distribution of microcracks in the specimen is still subjected to exponential distribution with some microcracks concentrated in certain regions. Finally, the change law of the fractal dimension of the local element in marble sample under different external load conditions is obtained by means of the statistical calculation of the fractal dimension.
文摘A kind of complex additive mainly containing Al, Mg, F, and O was prepared. The synthetical performances of the property-modified prebaked anodes containing additives were tested in laboratory. On the basis of ideal testing results obtained, a large number of industrial prebaked property-modified anodes are prepared in a large-scale aluminum company. Further more, they are all used in 160 kA prebaked anode aluminum electrolysis cells. The statistic result show that, compared with common anodes, the property-modified ones enhance current by 11.6 kg per ton aluminum averagely.
文摘High-temperature Ni-based alloys are widely used in the aerospace field due to their excellent properties,but the shortcomings of brittle fracture at the grain boundaries and poor plasticity at room temperature also limit their development to a certain extent.Researchers found that there areγ′precipitation phases similar to Ni_(3)Al in Pt-Al based alloys.In this paper,the CASTEP code of Materials Studio software package is used to simulate the thermal and mechanical properties ofγ′-Pt_(3)Al phase andγ′-Ni_(3)Al phase.By comparing the performance characteristics of the electronic structure,mechanical properties and point defect structure of the two,it is found that the stability,elastic deformation resistance and high temperature creep resistance of theγ′-Pt_(3)Al phase are better than those of theγ′-Ni_(3)Al phase.This will provide theoretical guidance for promoting the development of Pt-Al-based high-temperature materials.
基金Project(RG086/10AET) supported by the Institute of Research Management and Monitoring,University of Malaya,Malaysia
文摘Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE＇s theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE＇s theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design.
文摘There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that made by belt press.With the on-going improvement in technology,know-how & accumulated experiences, perhaps it’ s time for us to review the qualities & performances of synthetic diamond made by the cubic press more objectively.Studies were carried out on the performances of the two kinds of diamond by choosing from top brands & top qualities,with coarser mesh sizes 20/30 & 30/40.Comparisons were made on parameters, such as TI,TTI,PPC,bulk density,compact,roughness and arealight.And the diamonds chosen were used to produce the relevant diamond core drill bits and saw blades,their respective cutting performances such as cutting efficiency,segments consumption were measured and reported in this paper.The report demonstrates that producing the high quality diamond does not depend on the type of presses(Belt or Cubic) but rather on the know-how,technology and what it is made.
文摘Ⅰ. Introduction Over the past two decades, microwave remote sensing has evolved into a focal point in the remote sensing area. This is due to the fact that in microwave band, we can acquire physical parameters about ocean, terrain and atmosphere on all weather condition. Research and application work about the aerial passive micro wave remote sensors has been done at Changchun Institute of Geography since 1973, under the unitary planning of Academia Sinica. Microwave radiometers of six freqency bands have been developed. Numerous remote sensing experiments were carried out, and large amount of scientific data were accumulated. Recently, theoretical models have
文摘"Digital Earth"is one of integrated scientific technology based on development of information technology and modern space telemetry,and it possesses some special features such as application of great amount of geography data,which can describe the Earth in three dimensions and with higher resolution,i.e."virtual earth":the ordinary user also can readily obtain some information through certain means.Visualization and virtual reality are one
基金financially supported by the National Natural Science Foundation of China ( 11722220, 11672246,11472224)
文摘Background Traffic accidents,anti-terrorism,gas and chemical dangerous goods explosions,earthquake shock wave damage,and falling impacts in daily life and other events involving impact loads cause great harm to human organs and tissues,and even life-threatening.Such injuries are called impact damage.Although during the previous wars,the treatment of impact injuries has been greatly improved,and its treatment has been widely used in clinical practice.However,under the current development of society,the impact damage incident has not only been limited to the battlefield.Extreme organizations,frequent industrial production accidents,aircraft trains and other accidents have extended the impact damage incidents into daily society,seriously jeopardizing the health of civilians.Therefore,in order to better treat the injured organs under the impact load,such as the reconstruction and recovery of organ tissues,it is necessary to establish a corresponding system of clinical treatment methods for impact damage.In vitro models of traumatic injury are helping elucidate the pathobiological mechanisms responsible for dysfunction and delayed cell functional variation after mechanical stimulation of the single waveform pressure.It is likely that injury outcome is related to the biomechanical parameters of the traumatic event such as amplitudes and durations.However,the influence of impulsive pressure on endothelial function has not yet been fully studied in vitro.In this study,we developed a pressure loading device that produced positive by modifying an in vitro fluid percussion model and examined the effects of the pressures on macrophages’basic functions.Methods To model variations in the biomechanical injury parameters and simplify the experiment,single-use syringe was chosen to be the cell container and a drop hammer driven fluid percussion injury system(FPI)was designed and built to generate a single waveform with adjustable peak pressure and durations.Mice macrophage cells(Raw 264.7)were subjected to three types of the single positive pressure(120 kPa,550 kPa and 1 100 kPa).Every 12 hours we detected its basic functions(including phagocytosis and proliferative capacity)during the following 48 hours,also the immediate cell death.Results This single waveform pressure loading device could produce positive pressure with amplitudes of 70~1 200 kPa.After the pressure loading,there is no significant differences between the control cells and experiment cells.However,it does have a notable effect on its basic functions.The results showed that its phagocytosis and proliferative capacity were getting increased with a peak value on36 h and suddenly decreasing on 48 h.Moreover,these 4 regular curves are in proportion to the pressure.And the experimental results also indicate that the cell impact platform can achieve a single impact loading on the cells.The impact mainly causes the functional changes of RAW264.7 cells instead of directly causing its death.The cell proliferation activity and phagocytosis function are enhanced to some extent.Conclusions Those results indicate that single waveform pressure have a main effect on cell’s biological functions,not on cell death.And these effects on functions did have a regular functional rela-tionship.To explore more regular curves and the mechanism,we need more experiments such as genomics technical.
