The reform stems from honesty and determination. Since 2005, organ donation and transplantation in China has undergone thorough reform, which complies with legislation requirements and ethical principles established b...The reform stems from honesty and determination. Since 2005, organ donation and transplantation in China has undergone thorough reform, which complies with legislation requirements and ethical principles established by the World Health Organization(WHO). Reform in China has demonstrated the unwavering confidence and utmost determination of the Chinese government and the Chinese transplantation community. The year 2015 marked a historic turning point when voluntary donations from Chinese citizens became the sole legitimate source for organ transplantation. Since 2015, China has gradually established and refined the “Chinese Mode” and “China System” for organ donation and transplantation, fulfilling its political pledge of reform, and has garnered international recognition, and fostered a social culture which promotes organ donation. This article reviewed the history of reform on organ donation and transplantation in China, presented a new pattern of establishment of organ donation system in the new era of the country, and the direction of advances in the future.展开更多
Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride he...Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications.展开更多
1 Introduction Major and profound changes have taken place in China over the past 30 years. An epidemic of cardiovascular diseases （CVD） in China is emerging as a result of lifestyle changes, urbanization, and the ...1 Introduction Major and profound changes have taken place in China over the past 30 years. An epidemic of cardiovascular diseases （CVD） in China is emerging as a result of lifestyle changes, urbanization, and the accelerated process of aging. The incidence of CVD is continuously increasing and will remain an upward trend in the next decade. Since 2005,展开更多
1 Introduction Rapid socioeconomic progress has greatly affected the lifestyle in China.Consequently,owing to lifestyle changes,urbanization,and accelerated population aging,the risk of cardiovascular diseases(CVD)has...1 Introduction Rapid socioeconomic progress has greatly affected the lifestyle in China.Consequently,owing to lifestyle changes,urbanization,and accelerated population aging,the risk of cardiovascular diseases(CVD)has increased.The incidence of CVD has been increasing continuously and this upward trend is projected to continue in the next decade.The growing burden of CVD has become a major public health issue.展开更多
Objective: Measures of ventilation-co_2 output relationship have been shown to be more prognostic than peak O_2 uptake in assessing life expectancy in patients with chronic heart failure(CHF). Because both the ratios(...Objective: Measures of ventilation-co_2 output relationship have been shown to be more prognostic than peak O_2 uptake in assessing life expectancy in patients with chronic heart failure(CHF). Because both the ratios(V4e/V4co_2) and slopes(V4e-vs-V4co_2) of ventilation-co_2 output of differing durations can be used, we aim to ascertain which measurements best predicted CHF life expectancy. Methods: Two hundred and seventy-one CHF patients with NYHA class II-IV underwent incremental cardiopulmonary exercise testing(CPET) and were followed-up for a median duration of 479 days. Four different linear regression V4e-vsV4co_2 slopes were calculated from warm-up exercise onset to: 180 s, anaerobic threshold(AT), ventilatory compensation point(VCP); and peak exercise. Five V4e/V4co_2 ratios were calculated for the following durations: rest(120 s), warm-up(30 s), AT(60 s), lowest value(90 s), and peak exercise(30 s). Death or heart transplant were considered end-points. Multiple statistical analyses were performed. Results: CHF patients had high lowest V4e/V4co_2(41.0±9.2, 141±30%pred), high V4e/V4co_2 at AT(42.5±10.4, 145±35%pred), and high V4e-vs-V4co_2 slope to VCP(37.6±12.1, 126±41%pred). The best predictor of death was a higher lowest V4e/V4co_2(≥42, ≥141%pred), whereas the V4e-vs-V4co_2 slope to VCP was less variable than other slopes. For death prognosis in 6 months, %pred values were superior: for longer times, absolute values were superior. Conclusion: The increased lowest V4e/V4co_2 ratio easily identifiable and simply measured during exercise, is the best measurement to assess the ventilation-co_2 output relationship in prognosticating death in CHF patients.展开更多
Objective： The aim of our meta-analysis was to assess the effects of antiepileptic drugs on bone mineral density and bone metabolism in epileptic children. Methods： Searches of Pub Med and Web of Science were undert...Objective： The aim of our meta-analysis was to assess the effects of antiepileptic drugs on bone mineral density and bone metabolism in epileptic children. Methods： Searches of Pub Med and Web of Science were undertaken to identify studies evaluating the association between antiepileptic drugs and bone mineral density and bone metabolism. Results： A total of 22 studies with 1492 subjects were included in our research. We identified：（1） a reduction in bone mineral density at lumbar spine（standardized mean difference（SMD）=-0.30, 95% confidence interval（CI） [-0.61,-0.05]）, trochanter（mean difference（MD）=-0.07, 95% CI [-0.10,-0.05]）, femoral neck（MD=-0.05, 95% CI [-0.09,-0.02]）, and total body bone mineral density（MD=-0.33, 95% CI [-0.51,-0.15]）;（2） a reduction in 25-hydroxyvitamin D（MD=-3.37, 95% CI [-5.94,-0.80]） and an increase in serum alkaline phosphatase（SMD=0.71, 95% CI [0.38, 1.05]）;（3） no significant changes in serum parathyroid hormone, calcium, or phosphorus. Conclusions： Our meta-analysis suggests that treatment with antiepileptic drugs may be associated with decreased bone mineral density in epileptic children.展开更多
The effects of mass concentration and injection pressure on the atomization characteristics of low-viscosity fuel spray are studied in a constant-volume chamber.Microscopic spray parameters are measured by laser diffr...The effects of mass concentration and injection pressure on the atomization characteristics of low-viscosity fuel spray are studied in a constant-volume chamber.Microscopic spray parameters are measured by laser diffraction at different axial and radial positions downstream of the nozzle.The results show that the atomization effect is inhibited linearly with the increase of mass concentration.The increase of injection pressure promotes the droplet breakup.However,the trend gradually weakens and becomes more noticeable at high concentrations.Comparing with the concentration,the influence of the injection pressure on the atomization characteristics is dominant.Although low concentration and high injection pressure can promote the droplet breakup,they also increase the probability of droplet collision,resulting in droplet aggregation.This is more evident in low-viscosity fuels.The droplet size increases in the axial direction owing to the aggregation.However,the diameter decreases in the radial direction owing to the outward deflection of small droplets caused by air turbulence and entrainment.In addition,the high-velocity airflow significantly promotes the droplet breakup near the nozzle and spray axis regions and inhibits the aggregation effect.However,the lower-viscosity fuels keep smaller droplet sizes and better atomization in the whole spraying process,which is easier to realize than the higher-viscosity fuels.Overall,low concentration,high injection pressure,and low viscosity of fuel have beneficial effects on the droplet breakup.This is very important for improving the atomization effect of fuel.展开更多
A generalized simulation method of the tracking,telemetry and control（TT＆C） channel,which is applicable to wideband and arbitrary radio frequency（RF） signal,is proposed.It can accurately simulate the dynamic tran...A generalized simulation method of the tracking,telemetry and control（TT＆C） channel,which is applicable to wideband and arbitrary radio frequency（RF） signal,is proposed.It can accurately simulate the dynamic transmission delay of the arbitrary RF signal in channels,especially regardless of any prior knowledge including signal form,signal parameters,and so on.The proposed method orthogonally demodulates the wideband and arbitrary RF signal to complex baseband by a known local oscillator（LO） signal.Whereafter,it takes measures to obtain the delay reconstruction signal of baseband signals based on the dynamic transmission delay between a ground station and a responder.Meanwhile,it manages to obtain the delay reconstruction signal of LO signals.The simulation output signal（the delayed RF signal） can be achieved through the synthesis of the two delay reconstruction signals mentioned above.The principle and its related key technology are described in detail,and the realizable system architecture is given.展开更多
Phenomenon of localized surface plasmon excitation at nanostructured materials has attracted much attention in recent decades for their wide applications in single molecule detection,surface-enhanced Raman spectroscop...Phenomenon of localized surface plasmon excitation at nanostructured materials has attracted much attention in recent decades for their wide applications in single molecule detection,surface-enhanced Raman spectroscopy and nano-plasmonics.In addition to the excitation by external light field,an electron beam can also induce the local surface plasmon excitation.Nowadays,electron energy loss spectroscopy(EELS)technique has been increasingly employed in experiment to investigate the surface excitation characteristics of metallic nanoparticles.However,a present theoretical analysis tool for electromagnetic analysis based on the discrete dipole approximation(DDA)method can only treat the case of excitation by light field.In this work we extend the DDA method for the calculation of EELS spectrum for arbitary nanostructured materials.We have simulated EELS spectra for different incident locations of an electron beam on a single silver nanoparticle,the simulated results agree with an experimental measurement very well.The present method then provides a computation tool for study of the local surface plasmon excitation of metallic nanoparticles induced by an electron beam.展开更多
Electron inelastic mean free path （IMFP） is an important parameter for surface chemical quantification by surface electron spectroscopy techniques. It can be obtained from analysis of elastic peak electron spectrosc...Electron inelastic mean free path （IMFP） is an important parameter for surface chemical quantification by surface electron spectroscopy techniques. It can be obtained from analysis of elastic peak electron spectroscopy （EPES） spectra measured on samples and a Monte Carlo simulation method. To obtain IMFP parameters with high accuracy, the surface excitation effect on the measured EPES spectra has to be quantified as a surface excitation parameter （SEP）, which can be calculated via a dielectric response theory. However, such calculated SEP does not include influence of elastic scattering of electrons inside samples during their incidence and emission processes, which should not be neglected simply in determining IMFP by an EPES method. In this work a Monte Carlo simulation method is employed to determine surface excitation parameter by taking account of the elastic scattering effect. The simulated SEPs for different primary energies are found to be in good agreement with the experiments particularly for larger incident or emission angles above 60° where the elastic scattering effect plays a more important role than those in smaller incident or emission angles. Based on these new SEPs, the IMFP measurement by EPES technique can provide more accurate data.展开更多
Objective Fasting capillary blood glucose(CBG)must be measured before fluorodeoxyglucose-positron emission tomography(FDG-PET)imaging.In this study,we aimed to investigate whether a recently measured fasting venous bl...Objective Fasting capillary blood glucose(CBG)must be measured before fluorodeoxyglucose-positron emission tomography(FDG-PET)imaging.In this study,we aimed to investigate whether a recently measured fasting venous blood glucose(VBG)concentration could be substituted for CBG.Methods This retrospective study included 520 of 1,378 patients who had undergone FDG-PET at our institution in June 2022.None of the study patients had a history of diabetes mellitus.Each study patient’s CBG was measured immediately before FDG administration,whereas the VBG(VBG<7.8 mmol/L)was measured within one week before and after PET imaging.We used Bland−Altman plots to compare the two blood glucose concentrations.Results The 520 participants(315 male,205 female;ages 13-87 years)accounted for 37.7%(520/1378)of all patients.The median CBG and VBG were 5.7 mmol/L(interquartile range,5.2-6.2 mmol/L)and 5.1 mmol/L(interquartile range,4.8-5.8 mmol/L),respectively.There was a moderate positive correlation between CBG and VBG(r=0.4370,95%CI:0.3625-0.5059,P<0.0001).Bland-Altman plots revealed that only 5.8%(30/520)of the dots exceeded the 95%limits of agreement and these were all within acceptable limits,indicating that the bias was not clinically significant.Conclusion When performing FDG-PET on patients without diabetes,a VBG of<7.8 mmol/L within the previous week may be an acceptable alternative to CBG.展开更多
To the Editor:Heart transplantation is rapidly developing all around the world and has helped thousands of patients with end-stage heart disease.In China,the annual number of heart transplantations in the Chinese main...To the Editor:Heart transplantation is rapidly developing all around the world and has helped thousands of patients with end-stage heart disease.In China,the annual number of heart transplantations in the Chinese mainland has steadily increased since 2015,from 279 in 2015 to 557 in 2020.[1]However,compared with developed countries,developing countries like China had no sufficient foundation of transplant system and generally faced three problems,including severe shortage of donor organs,lack of organ allocation system,and quality control system.To solve the above problems,China government launched a series of reforms in organ donation,allocation,and medical quality control between 2005 and 2015,and a scientific and standardized transplantation system was established.However,few data were published to evaluate the current situation after the system reform.展开更多
On June 24,2021,a 40-year-old reinforced concrete flat plate structure building in Miami suffered a sudden partial collapse.This study analyzed the overall performance and key components of the collapsed building base...On June 24,2021,a 40-year-old reinforced concrete flat plate structure building in Miami suffered a sudden partial collapse.This study analyzed the overall performance and key components of the collapsed building based on the building design codes(ACI-318 and GB 50010).Punching shear and post-punching performances of typical slabcolumn joints are also studied through the refined finite element analysis.The collapse process was simulated and visualized using a physics engine.By way of these analyses,weak design points of the collapsed building are highlighted.The differences between the reinforcement detailing of the collapsed building and the requirements of the current Chinese code are discussed,together with a comparison of the punching shear and post-punching performances.The simulated collapse procedure and debris distribution are compared with the actual collapse scenes.展开更多
This study aims to construct a logistically derived additive score for predicting in-hospital mortality risk in Chinese patients undergoing coronary artery bypass surgery(CABG).Data from 9839 consecutive CABG patients...This study aims to construct a logistically derived additive score for predicting in-hospital mortality risk in Chinese patients undergoing coronary artery bypass surgery(CABG).Data from 9839 consecutive CABG patients in 43 Chinese centers were collected between 2007 and 2008 from the Chinese Coronary Artery Bypass Grafting Registry.This database was randomly divided into developmental and validation subsets(9:1).The data in the developmental dataset were used to develop the model using logistic regression.Calibration and discrimination characteristics were assessed using the validation dataset.Thresholds were defined for each model to distinguish different risk groups.After excluding 275 patients with incomplete information,the overall mortality rate of the remaining 9564 patients was 2.5%.The SinoSCORE model was constructed based on 11 variables:age,preoperative NYHA stageⅢorⅣ,chronic renal failure,extracardiac arteriopathy,chronic obstructive pulmonary disease,preoperative atrial fibrillation or flutter(within 2 weeks),left ventricular ejection fraction,other elective surgery,combined valve procedures,preoperative critical state,and BMI.In the developmental dataset,calibration using a Hosmer-Lemeshow(HL)test was at P=0.44 and discrimination based on the area under the receiver operating characteristic curve(ROC)was 0.80.In the validation dataset,the HL test was at P=0.34 and the area under the ROC(AUC)was 0.78.A logistically derived additive model for predicting in-hospital mortality among Chinese patients undergoing CABG was developed based on the most up-to-date multi-center data from China.展开更多
Introduction Albumin,which is a 65-kDa liver-synthesized protein,accounts for nearly 50%of total plasma protein and contributes to approximately 80%of intravascular oncotic pressure.Albumin helps maintain microvascula...Introduction Albumin,which is a 65-kDa liver-synthesized protein,accounts for nearly 50%of total plasma protein and contributes to approximately 80%of intravascular oncotic pressure.Albumin helps maintain microvascular integrity,functions as an antioxidant,and transports hormones,fatty acid,bile salts,bilirubin,electrolytes(e.g.,calcium,magnesium,copper,zinc,et al.),and drugs.[1–3]Human serum albumin(HSA)is a sterile,liquid albumin product derived from large pools of human plasma by fractionation and pasteurization.The medical use of HAS could date back to approximately the time of World War II.展开更多
Background::Imprecise interpretation of coronary angiograms was reported and resulted in inappropriate revascularization.Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery(SYNTAX)score i...Background::Imprecise interpretation of coronary angiograms was reported and resulted in inappropriate revascularization.Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery(SYNTAX)score is a comprehensive system to evaluate the complexity of the overall lesions.We hypothesized that a real-time SYNTAX score feedback from image analysts may rectify the mis-estimation and improve revascularization appropriateness in patients with stable coronary artery disease(CAD).Methods::In this single-center,historical control study,patients with stable CAD with coronary lesion stenosis≥50%were consecutively recruited.During the control period,SYNTAX scores were calculated by treating cardiologists.During the intervention period,SYNTAX scores were calculated by image analysts immediately after coronary angiography and were provided to cardiologists in real-time to aid decision-making.The primary outcome was revascularization deemed inappropriate by Chinese appropriate use criteria for coronary revascularization.Results::A total of 3245 patients were enrolled and assigned to the control group(08/2016-03/2017,n=1525)or the intervention group(03/2017-09/2017,n=1720).For SYNTAX score tertiles,17.9%patients were overestimated and 4.3%were underestimated by cardiologists in the control group.After adjustment,inappropriate revascularization significantly decreased in the intervention group compared with the control group(adjusted odds ratio[OR]:0.83;95%confidence interval[CI]:0.73-0.95;P=0.007).Both inappropriate percutaneous coronary intervention(adjusted OR:0.82;95%CI:0.74-0.92;P<0.001)and percutaneous coronary intervention utilization(adjusted OR:0.88;95%CI:0.79-0.98;P=0.016)decreased significantly in the intervention group.There was no significant difference in 1-year adverse cardiac events between the control group and the intervention group.Conclusions::Real-time SYNTAX score feedback significantly reduced inappropriate coronary revascularization in stable patients with CAD.Clinical trial registration::Nos.NCT03068858 and NCT02880605;https://www.clinicaltrials.gov.展开更多
Resistance to unexpected disasters and rapid post-disaster recovery(i.e.,disaster resilience)of cities are extremely necessary owing to the concentrated risk of urbanization.Resilience quantification can adequately re...Resistance to unexpected disasters and rapid post-disaster recovery(i.e.,disaster resilience)of cities are extremely necessary owing to the concentrated risk of urbanization.Resilience quantification can adequately reflect the capacity of a city to withstand disasters.Many existing studies have focused on and proposed several frameworks on the quantitative measures of disaster resilience,and the corresponding research objects include different types of disasters(e.g.,earthquake,hurricane,flood,and fire),various domains(e.g.,engineering,social,and economic),and multiple levels(e.g.,city,community,and building).Among these research objects,studies on seismic resilience in civil engineering are relatively comprehensive.Specifically,studies on resilience in civil engineering have paid significant attention to the dynamics of engineering facilities and the engineering-related social and economic functions,including city-scale engineering,social,and economic functionalities,and essential functionalities of building,transportation,lifeline,and nonphysical subsystems of a city.Consequently,based on the review of resilience studies carried out in recent years,the framework and specifications for the quantification of disaster resilience of civil engineering systems subjected to earthquakes and other unexpected disasters are elaborated.Methods of disaster resilience assessment of cities and the corresponding subsystems are discussed.Furthermore,several case studies are reviewed,and resilience limit-state analyses of communities and buildings are performed.展开更多
Conjugated polymers attracted much attention in the past few decades due to their wide applications in various optoelectronic devices and circuits. The charge transport process in conjugated polymers mainly occurs in ...Conjugated polymers attracted much attention in the past few decades due to their wide applications in various optoelectronic devices and circuits. The charge transport process in conjugated polymers mainly occurs in the intrachain and interchain parts, where the interchain charge transport is generally slower than intrachain transport and may slow down the whole charge transport properties. Aiming at this issue, herein we employ semiconducting single-walled carbon nanotubes(s-SWNTs) as efficient charge-transporting jointing channels between conjugated polymer chains for improving the charge transport performance. Taking the typical conjugated polymer, ploy-N-alkyl-diketopyrrolopyrrole-dithienylthieno[3,2-b]thiophene(PDPP-TT) as an example, polymer thin film transistors(PTFTs) based on the optimized blended films of PDPP-TT/s-SWNTs exhibit an obviously increasing device performance compared with the devices based on pure PDPP-TT films, with the hole and electron mobility increased from 2.32 to 12.32 cm^2 V^-1 s^-1 and from 2.02 to 5.77 cm^2 V^-1 s^-1, respectively. This result suggests the importance of forming continuous conducting channels in conjugated polymer thin films, which can also be extended to other polymeric electronic and optoelectronic devices to promote their potential applications in large-area, low-cost and high performance polymeric electronic devices and circuits.展开更多
Previous research has found that electrical conductivity(EC),an important index to predict meat freshness and shelflife,is very promising for estimating the late postmortem interval(PMI).However,whether it has potenti...Previous research has found that electrical conductivity(EC),an important index to predict meat freshness and shelflife,is very promising for estimating the late postmortem interval(PMI).However,whether it has potential use in the early PMI has not been fully studied yet.To test this possibility in the present study,EC of three internal organs of rat liver,spleen,and kidney were determined within 24 postmortem hows,and then,EC changes at different PMIs were carefully analyzed.The overall results showed that EC of liver and spleen increased significantly with PMI while EC of kidney had minor changes during the same period.Specifically,significant linear positive correlations between EC of liver and spleen and PMI were found and the coefficients of their regression functions were R^(2)=0.98 and R^(2)=0.95,respectively.It can be concluded that determination of EC in certain internal organs such as liver and spleen may be a potential tool in the early PMI estimation.However,more researches on its influencing factors are needed to facilitate its final use in practice.展开更多
文摘The reform stems from honesty and determination. Since 2005, organ donation and transplantation in China has undergone thorough reform, which complies with legislation requirements and ethical principles established by the World Health Organization(WHO). Reform in China has demonstrated the unwavering confidence and utmost determination of the Chinese government and the Chinese transplantation community. The year 2015 marked a historic turning point when voluntary donations from Chinese citizens became the sole legitimate source for organ transplantation. Since 2015, China has gradually established and refined the “Chinese Mode” and “China System” for organ donation and transplantation, fulfilling its political pledge of reform, and has garnered international recognition, and fostered a social culture which promotes organ donation. This article reviewed the history of reform on organ donation and transplantation in China, presented a new pattern of establishment of organ donation system in the new era of the country, and the direction of advances in the future.
基金supported by the National Natural Science Foundation of China(No.22465009)the Education Department of Guizhou Province(No.2021312)the Foundation of Guizhou Province(No.2019-5666).
文摘Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications.
文摘1 Introduction Major and profound changes have taken place in China over the past 30 years. An epidemic of cardiovascular diseases （CVD） in China is emerging as a result of lifestyle changes, urbanization, and the accelerated process of aging. The incidence of CVD is continuously increasing and will remain an upward trend in the next decade. Since 2005,
文摘1 Introduction Rapid socioeconomic progress has greatly affected the lifestyle in China.Consequently,owing to lifestyle changes,urbanization,and accelerated population aging,the risk of cardiovascular diseases(CVD)has increased.The incidence of CVD has been increasing continuously and this upward trend is projected to continue in the next decade.The growing burden of CVD has become a major public health issue.
基金partially supported by National Center of Cardiovascular Diseases,Fuwai Hospital,Chinese Academy of Medical Sciences,Beijing,ChinaThe clinical trials of the Resynchronization for Hemod Ynamic Treatment for Heart Failure Management(RHYTHM)[38]were funded by St Jude Medical
文摘Objective: Measures of ventilation-co_2 output relationship have been shown to be more prognostic than peak O_2 uptake in assessing life expectancy in patients with chronic heart failure(CHF). Because both the ratios(V4e/V4co_2) and slopes(V4e-vs-V4co_2) of ventilation-co_2 output of differing durations can be used, we aim to ascertain which measurements best predicted CHF life expectancy. Methods: Two hundred and seventy-one CHF patients with NYHA class II-IV underwent incremental cardiopulmonary exercise testing(CPET) and were followed-up for a median duration of 479 days. Four different linear regression V4e-vsV4co_2 slopes were calculated from warm-up exercise onset to: 180 s, anaerobic threshold(AT), ventilatory compensation point(VCP); and peak exercise. Five V4e/V4co_2 ratios were calculated for the following durations: rest(120 s), warm-up(30 s), AT(60 s), lowest value(90 s), and peak exercise(30 s). Death or heart transplant were considered end-points. Multiple statistical analyses were performed. Results: CHF patients had high lowest V4e/V4co_2(41.0±9.2, 141±30%pred), high V4e/V4co_2 at AT(42.5±10.4, 145±35%pred), and high V4e-vs-V4co_2 slope to VCP(37.6±12.1, 126±41%pred). The best predictor of death was a higher lowest V4e/V4co_2(≥42, ≥141%pred), whereas the V4e-vs-V4co_2 slope to VCP was less variable than other slopes. For death prognosis in 6 months, %pred values were superior: for longer times, absolute values were superior. Conclusion: The increased lowest V4e/V4co_2 ratio easily identifiable and simply measured during exercise, is the best measurement to assess the ventilation-co_2 output relationship in prognosticating death in CHF patients.
基金Project supported by the National High-Tech R&D Program(863)of China(No.2012AA020408)the Medical and Health General Research Plan of Zhejiang Province(No.2014KYA103),China
文摘Objective： The aim of our meta-analysis was to assess the effects of antiepileptic drugs on bone mineral density and bone metabolism in epileptic children. Methods： Searches of Pub Med and Web of Science were undertaken to identify studies evaluating the association between antiepileptic drugs and bone mineral density and bone metabolism. Results： A total of 22 studies with 1492 subjects were included in our research. We identified：（1） a reduction in bone mineral density at lumbar spine（standardized mean difference（SMD）=-0.30, 95% confidence interval（CI） [-0.61,-0.05]）, trochanter（mean difference（MD）=-0.07, 95% CI [-0.10,-0.05]）, femoral neck（MD=-0.05, 95% CI [-0.09,-0.02]）, and total body bone mineral density（MD=-0.33, 95% CI [-0.51,-0.15]）;（2） a reduction in 25-hydroxyvitamin D（MD=-3.37, 95% CI [-5.94,-0.80]） and an increase in serum alkaline phosphatase（SMD=0.71, 95% CI [0.38, 1.05]）;（3） no significant changes in serum parathyroid hormone, calcium, or phosphorus. Conclusions： Our meta-analysis suggests that treatment with antiepileptic drugs may be associated with decreased bone mineral density in epileptic children.
基金Project supported by the Young Scientists Fund of National Natural Science Foundation of China(Grant No.11802136).
文摘The effects of mass concentration and injection pressure on the atomization characteristics of low-viscosity fuel spray are studied in a constant-volume chamber.Microscopic spray parameters are measured by laser diffraction at different axial and radial positions downstream of the nozzle.The results show that the atomization effect is inhibited linearly with the increase of mass concentration.The increase of injection pressure promotes the droplet breakup.However,the trend gradually weakens and becomes more noticeable at high concentrations.Comparing with the concentration,the influence of the injection pressure on the atomization characteristics is dominant.Although low concentration and high injection pressure can promote the droplet breakup,they also increase the probability of droplet collision,resulting in droplet aggregation.This is more evident in low-viscosity fuels.The droplet size increases in the axial direction owing to the aggregation.However,the diameter decreases in the radial direction owing to the outward deflection of small droplets caused by air turbulence and entrainment.In addition,the high-velocity airflow significantly promotes the droplet breakup near the nozzle and spray axis regions and inhibits the aggregation effect.However,the lower-viscosity fuels keep smaller droplet sizes and better atomization in the whole spraying process,which is easier to realize than the higher-viscosity fuels.Overall,low concentration,high injection pressure,and low viscosity of fuel have beneficial effects on the droplet breakup.This is very important for improving the atomization effect of fuel.
基金supported by the Foundation of Shanghai Aerospace Science and Technology(20120541088)
文摘A generalized simulation method of the tracking,telemetry and control（TT＆C） channel,which is applicable to wideband and arbitrary radio frequency（RF） signal,is proposed.It can accurately simulate the dynamic transmission delay of the arbitrary RF signal in channels,especially regardless of any prior knowledge including signal form,signal parameters,and so on.The proposed method orthogonally demodulates the wideband and arbitrary RF signal to complex baseband by a known local oscillator（LO） signal.Whereafter,it takes measures to obtain the delay reconstruction signal of baseband signals based on the dynamic transmission delay between a ground station and a responder.Meanwhile,it manages to obtain the delay reconstruction signal of LO signals.The simulation output signal（the delayed RF signal） can be achieved through the synthesis of the two delay reconstruction signals mentioned above.The principle and its related key technology are described in detail,and the realizable system architecture is given.
基金supported by the National Natural Science Foundation of China (No.11574289)Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund(2nd phase) (No.U1501501)+1 种基金"111" Project by Education Ministry of China"Materials research by Information Integration" Initiative (MI2I) Project of the Support Program for Starting Up Innovation Hub from Japan Science and Technology Agency (JST)
文摘Phenomenon of localized surface plasmon excitation at nanostructured materials has attracted much attention in recent decades for their wide applications in single molecule detection,surface-enhanced Raman spectroscopy and nano-plasmonics.In addition to the excitation by external light field,an electron beam can also induce the local surface plasmon excitation.Nowadays,electron energy loss spectroscopy(EELS)technique has been increasingly employed in experiment to investigate the surface excitation characteristics of metallic nanoparticles.However,a present theoretical analysis tool for electromagnetic analysis based on the discrete dipole approximation(DDA)method can only treat the case of excitation by light field.In this work we extend the DDA method for the calculation of EELS spectrum for arbitary nanostructured materials.We have simulated EELS spectra for different incident locations of an electron beam on a single silver nanoparticle,the simulated results agree with an experimental measurement very well.The present method then provides a computation tool for study of the local surface plasmon excitation of metallic nanoparticles induced by an electron beam.
基金This work was supported by the National Natural Science Foundation of China （No.11274288 and No.11574289）. We thank the Supercomputing Center of USTC for support in performing parallel computations.
文摘Electron inelastic mean free path （IMFP） is an important parameter for surface chemical quantification by surface electron spectroscopy techniques. It can be obtained from analysis of elastic peak electron spectroscopy （EPES） spectra measured on samples and a Monte Carlo simulation method. To obtain IMFP parameters with high accuracy, the surface excitation effect on the measured EPES spectra has to be quantified as a surface excitation parameter （SEP）, which can be calculated via a dielectric response theory. However, such calculated SEP does not include influence of elastic scattering of electrons inside samples during their incidence and emission processes, which should not be neglected simply in determining IMFP by an EPES method. In this work a Monte Carlo simulation method is employed to determine surface excitation parameter by taking account of the elastic scattering effect. The simulated SEPs for different primary energies are found to be in good agreement with the experiments particularly for larger incident or emission angles above 60° where the elastic scattering effect plays a more important role than those in smaller incident or emission angles. Based on these new SEPs, the IMFP measurement by EPES technique can provide more accurate data.
基金This study was supported by Shanghai Municipal Key Clinical Specialty(No.shslczdzk03401).
文摘Objective Fasting capillary blood glucose(CBG)must be measured before fluorodeoxyglucose-positron emission tomography(FDG-PET)imaging.In this study,we aimed to investigate whether a recently measured fasting venous blood glucose(VBG)concentration could be substituted for CBG.Methods This retrospective study included 520 of 1,378 patients who had undergone FDG-PET at our institution in June 2022.None of the study patients had a history of diabetes mellitus.Each study patient’s CBG was measured immediately before FDG administration,whereas the VBG(VBG<7.8 mmol/L)was measured within one week before and after PET imaging.We used Bland−Altman plots to compare the two blood glucose concentrations.Results The 520 participants(315 male,205 female;ages 13-87 years)accounted for 37.7%(520/1378)of all patients.The median CBG and VBG were 5.7 mmol/L(interquartile range,5.2-6.2 mmol/L)and 5.1 mmol/L(interquartile range,4.8-5.8 mmol/L),respectively.There was a moderate positive correlation between CBG and VBG(r=0.4370,95%CI:0.3625-0.5059,P<0.0001).Bland-Altman plots revealed that only 5.8%(30/520)of the dots exceeded the 95%limits of agreement and these were all within acceptable limits,indicating that the bias was not clinically significant.Conclusion When performing FDG-PET on patients without diabetes,a VBG of<7.8 mmol/L within the previous week may be an acceptable alternative to CBG.
基金supported by a grant of the National Clinical Research Center for Cardiovascular Diseases,Fuwai Hospital,Chinese Academy of Medical Sciences(No.2023002).
文摘To the Editor:Heart transplantation is rapidly developing all around the world and has helped thousands of patients with end-stage heart disease.In China,the annual number of heart transplantations in the Chinese mainland has steadily increased since 2015,from 279 in 2015 to 557 in 2020.[1]However,compared with developed countries,developing countries like China had no sufficient foundation of transplant system and generally faced three problems,including severe shortage of donor organs,lack of organ allocation system,and quality control system.To solve the above problems,China government launched a series of reforms in organ donation,allocation,and medical quality control between 2005 and 2015,and a scientific and standardized transplantation system was established.However,few data were published to evaluate the current situation after the system reform.
基金the financial support received from The National Key R&D Program(No.2019YFE0112800)the National Natural Science Foundation of China(Grant No.51778341)the Australian Research Council through an ARC Discovery Project(No.DP150100606).
文摘On June 24,2021,a 40-year-old reinforced concrete flat plate structure building in Miami suffered a sudden partial collapse.This study analyzed the overall performance and key components of the collapsed building based on the building design codes(ACI-318 and GB 50010).Punching shear and post-punching performances of typical slabcolumn joints are also studied through the refined finite element analysis.The collapse process was simulated and visualized using a physics engine.By way of these analyses,weak design points of the collapsed building are highlighted.The differences between the reinforcement detailing of the collapsed building and the requirements of the current Chinese code are discussed,together with a comparison of the punching shear and post-punching performances.The simulated collapse procedure and debris distribution are compared with the actual collapse scenes.
基金supported by the Key Project in the National Science&Technology Pillar Program during the 12th 5-Year Plan Period(2011BAI11B21,2011BAI11B02)Public Specialty Fund of Health Ministry(200902001)and Program for New Century Excellent Talents in University.
文摘This study aims to construct a logistically derived additive score for predicting in-hospital mortality risk in Chinese patients undergoing coronary artery bypass surgery(CABG).Data from 9839 consecutive CABG patients in 43 Chinese centers were collected between 2007 and 2008 from the Chinese Coronary Artery Bypass Grafting Registry.This database was randomly divided into developmental and validation subsets(9:1).The data in the developmental dataset were used to develop the model using logistic regression.Calibration and discrimination characteristics were assessed using the validation dataset.Thresholds were defined for each model to distinguish different risk groups.After excluding 275 patients with incomplete information,the overall mortality rate of the remaining 9564 patients was 2.5%.The SinoSCORE model was constructed based on 11 variables:age,preoperative NYHA stageⅢorⅣ,chronic renal failure,extracardiac arteriopathy,chronic obstructive pulmonary disease,preoperative atrial fibrillation or flutter(within 2 weeks),left ventricular ejection fraction,other elective surgery,combined valve procedures,preoperative critical state,and BMI.In the developmental dataset,calibration using a Hosmer-Lemeshow(HL)test was at P=0.44 and discrimination based on the area under the receiver operating characteristic curve(ROC)was 0.80.In the validation dataset,the HL test was at P=0.34 and the area under the ROC(AUC)was 0.78.A logistically derived additive model for predicting in-hospital mortality among Chinese patients undergoing CABG was developed based on the most up-to-date multi-center data from China.
文摘Introduction Albumin,which is a 65-kDa liver-synthesized protein,accounts for nearly 50%of total plasma protein and contributes to approximately 80%of intravascular oncotic pressure.Albumin helps maintain microvascular integrity,functions as an antioxidant,and transports hormones,fatty acid,bile salts,bilirubin,electrolytes(e.g.,calcium,magnesium,copper,zinc,et al.),and drugs.[1–3]Human serum albumin(HSA)is a sterile,liquid albumin product derived from large pools of human plasma by fractionation and pasteurization.The medical use of HAS could date back to approximately the time of World War II.
基金This work was supported by grants from the Capital’S Funds for Health Improvement and Research(No.2016-1-4031)National Key Research and Development Program(No.2016YFC1302000)Beijing Municipal Commission of Science and Technology Project(No.D171100002917001).
文摘Background::Imprecise interpretation of coronary angiograms was reported and resulted in inappropriate revascularization.Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery(SYNTAX)score is a comprehensive system to evaluate the complexity of the overall lesions.We hypothesized that a real-time SYNTAX score feedback from image analysts may rectify the mis-estimation and improve revascularization appropriateness in patients with stable coronary artery disease(CAD).Methods::In this single-center,historical control study,patients with stable CAD with coronary lesion stenosis≥50%were consecutively recruited.During the control period,SYNTAX scores were calculated by treating cardiologists.During the intervention period,SYNTAX scores were calculated by image analysts immediately after coronary angiography and were provided to cardiologists in real-time to aid decision-making.The primary outcome was revascularization deemed inappropriate by Chinese appropriate use criteria for coronary revascularization.Results::A total of 3245 patients were enrolled and assigned to the control group(08/2016-03/2017,n=1525)or the intervention group(03/2017-09/2017,n=1720).For SYNTAX score tertiles,17.9%patients were overestimated and 4.3%were underestimated by cardiologists in the control group.After adjustment,inappropriate revascularization significantly decreased in the intervention group compared with the control group(adjusted odds ratio[OR]:0.83;95%confidence interval[CI]:0.73-0.95;P=0.007).Both inappropriate percutaneous coronary intervention(adjusted OR:0.82;95%CI:0.74-0.92;P<0.001)and percutaneous coronary intervention utilization(adjusted OR:0.88;95%CI:0.79-0.98;P=0.016)decreased significantly in the intervention group.There was no significant difference in 1-year adverse cardiac events between the control group and the intervention group.Conclusions::Real-time SYNTAX score feedback significantly reduced inappropriate coronary revascularization in stable patients with CAD.Clinical trial registration::Nos.NCT03068858 and NCT02880605;https://www.clinicaltrials.gov.
基金The authors are grateful for the financial support from the National Natural Science Founda-tion of China(No.U1709212)the Tencent Foundation through the XPLORER PRIZE.
文摘Resistance to unexpected disasters and rapid post-disaster recovery(i.e.,disaster resilience)of cities are extremely necessary owing to the concentrated risk of urbanization.Resilience quantification can adequately reflect the capacity of a city to withstand disasters.Many existing studies have focused on and proposed several frameworks on the quantitative measures of disaster resilience,and the corresponding research objects include different types of disasters(e.g.,earthquake,hurricane,flood,and fire),various domains(e.g.,engineering,social,and economic),and multiple levels(e.g.,city,community,and building).Among these research objects,studies on seismic resilience in civil engineering are relatively comprehensive.Specifically,studies on resilience in civil engineering have paid significant attention to the dynamics of engineering facilities and the engineering-related social and economic functions,including city-scale engineering,social,and economic functionalities,and essential functionalities of building,transportation,lifeline,and nonphysical subsystems of a city.Consequently,based on the review of resilience studies carried out in recent years,the framework and specifications for the quantification of disaster resilience of civil engineering systems subjected to earthquakes and other unexpected disasters are elaborated.Methods of disaster resilience assessment of cities and the corresponding subsystems are discussed.Furthermore,several case studies are reviewed,and resilience limit-state analyses of communities and buildings are performed.
基金financial support from the Ministry of Science and Technology of China (2017YFA0204503 and 2016YFB0401100)the National Natural Science Foundation of China (51725304, 51633006, 51703159, 51733004 and 21875259)+1 种基金the Strategic Priority Research Program (XDB12030300)the Chinese Academy of Sciences and the National Program for Support of Top-notch Young Professionals
文摘Conjugated polymers attracted much attention in the past few decades due to their wide applications in various optoelectronic devices and circuits. The charge transport process in conjugated polymers mainly occurs in the intrachain and interchain parts, where the interchain charge transport is generally slower than intrachain transport and may slow down the whole charge transport properties. Aiming at this issue, herein we employ semiconducting single-walled carbon nanotubes(s-SWNTs) as efficient charge-transporting jointing channels between conjugated polymer chains for improving the charge transport performance. Taking the typical conjugated polymer, ploy-N-alkyl-diketopyrrolopyrrole-dithienylthieno[3,2-b]thiophene(PDPP-TT) as an example, polymer thin film transistors(PTFTs) based on the optimized blended films of PDPP-TT/s-SWNTs exhibit an obviously increasing device performance compared with the devices based on pure PDPP-TT films, with the hole and electron mobility increased from 2.32 to 12.32 cm^2 V^-1 s^-1 and from 2.02 to 5.77 cm^2 V^-1 s^-1, respectively. This result suggests the importance of forming continuous conducting channels in conjugated polymer thin films, which can also be extended to other polymeric electronic and optoelectronic devices to promote their potential applications in large-area, low-cost and high performance polymeric electronic devices and circuits.
基金This study was supported by the Basic and Frontier Study of Technology Project of Henan Province(Grant No.112300410082)the Doctor Foundation and the Youngs'Foundation of Henan University of Science and Technology(Grant No.09001309,2013ZCX024 and 2011QN52)Key Laboratory of Forensic Medicine Identification in Luoyang(No.11550002).
文摘Previous research has found that electrical conductivity(EC),an important index to predict meat freshness and shelflife,is very promising for estimating the late postmortem interval(PMI).However,whether it has potential use in the early PMI has not been fully studied yet.To test this possibility in the present study,EC of three internal organs of rat liver,spleen,and kidney were determined within 24 postmortem hows,and then,EC changes at different PMIs were carefully analyzed.The overall results showed that EC of liver and spleen increased significantly with PMI while EC of kidney had minor changes during the same period.Specifically,significant linear positive correlations between EC of liver and spleen and PMI were found and the coefficients of their regression functions were R^(2)=0.98 and R^(2)=0.95,respectively.It can be concluded that determination of EC in certain internal organs such as liver and spleen may be a potential tool in the early PMI estimation.However,more researches on its influencing factors are needed to facilitate its final use in practice.
