Gastric cancer is one of the most common malignant tumors,for patients with advanced gastric cancer,the traditional treatment is mainly chemotherapy or combined targeted therapy;however,these have not achieved ideal e...Gastric cancer is one of the most common malignant tumors,for patients with advanced gastric cancer,the traditional treatment is mainly chemotherapy or combined targeted therapy;however,these have not achieved ideal efficacy.However,with the continuous deepening of research on molecular targeted drugs and immunosuppressants,the treatment of advanced gastric cancer patients has made new progress,and some new technologies have also been continuously emerged and applied,which brings hope for the treatment of advanced gastric cancer.Recently,several multicenter randomized controlled phase III studies on immunotherapy for advanced gastric cancer yielded encouraging results,demonstrating its superior efficacy in the treatment of advanced gastric cancer.However,prospective data to support the acceptance of surgery and the R0 removal rate following conversion therapy with immune checkpoint inhibitors are lacking.In this study,a 58-year-old woman with advanced gastric cancer and positive PD-L1 expression,negative HER-2 expression,and microsatellite stable status received immunochemotherapy combined with traditional Chinese medicine to achieve R0 resection and satisfactory efficacy.展开更多
Aqueous ammonia(NH3) is a promising alternative solvent for the capture of industrial CO_2 emissions, given its high chemical stability and CO_2 removal capacity, and low material costs and regeneration energy. NH3 al...Aqueous ammonia(NH3) is a promising alternative solvent for the capture of industrial CO_2 emissions, given its high chemical stability and CO_2 removal capacity, and low material costs and regeneration energy. NH3 also has potential for capturing multiple flue gas components, including NOx, SOxand CO_2, and producing value-added chemicals. However, its high volatility and low reactivity towards CO_2 limit its economic viability. Considerable efforts have been made to advance aqueous NH3-based post-combustion capture technologies in the last few years: in particular, General Electric's chilled NH3 process, CSIRO's mild-temperature aqueous NH3 process and SRI International's mixed-salts(NH3 and potassium carbonate) technology. Here, we review these research activities and other developments in the field, and outline future research needed to further improve aqueous NH3-based CO_2 capture technologies.展开更多
The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low...The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low-speed model test. However, this method is problematic for ships with bulbous bows and transom. In this article, a Computational Fluid Dynamics(CFD)-based method is introduced to obtain k for different type of ships at different drafts, and a comparison is made between the CFD method and the model test. The results show that the CFD method produces reasonable k values. A grid generating method and turbulence model are briefly discussed in the context of obtaining a consistent k using CFD.展开更多
Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the Haber-Bosch process.Unfortunately,the electrochemical ...Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the Haber-Bosch process.Unfortunately,the electrochemical N2 reduction reaction(NRR)method as a rising approach currently still shows low selectivity(Faradaic efficiency<10%)and high-energy consumption[applied potential at least-0.2 V versus the reversible hydrogen electrode(RHE)].Here,the role of molybdenum aluminum boride single crystals,belonging to a family of ternary transition metal aluminum borides known as MAB phases,is reported for the electrochemical NRR for the first time,at a low applied potential(-0.05 V versus RHE)under ambient conditions and in alkaline media.Due to the unique nano-laminated crystal structure of the MAB phase,these inexpensive materials have been found to exhibit excellent electrocatalytic performances(NH3 yield:9.2μg h^-1cm^-2mgcat^-1.,Faradaic efficiency:30.1%)at the low overpotential,and to display a high chemical stability and sustained catalytic performance.In conjunction,further mechanism studies indicate B and Al as main-group metals show a highly selective affinity to N2 due to the strong interaction between the B 2p/Al 3p band and the N 2p orbitals,while Mo exhibits specific catalytic activity toward the subsequent reduction reaction.Overall,the MAB-phase catalyst under the synergy of the elements within ternary compound can suppress the hydrogen evolution reaction and achieve enhanced NRR performance.The significance of this work is to provide a promising candidate in the future synthesis of ammonia.展开更多
Molecular simulation plays an increasingly important role in studying the properties of complex fluid systems containing charges,such as ions,piezoelectric materials,ionic liquids,ionic surfactants,polyelectrolytes,zw...Molecular simulation plays an increasingly important role in studying the properties of complex fluid systems containing charges,such as ions,piezoelectric materials,ionic liquids,ionic surfactants,polyelectrolytes,zwitterionic materials,nucleic acids,proteins,biomembranes and etc.,where the electrostatic interactions are of special significance.Several methods have been available for treating the electrostatic interactions in explicit and implicit solvent models.Accurate and efficient treatment of such interactions has therefore always been one of the most challenging issues in classical molecular dynamics simulations due to their inhomogeneity and long-range characteristics.Currently,two major challenges remain in the application field of electrostatic interactions in molecular simulations;(i)improving the representation of electrostatic interactions while reducing the computational costs in molecular simulations;(ii)revealing the role of electrostatic interactions in regulating the specific properties of complex fluids.In this review,the calculation methods of electrostatic interactions,including basic principles,applicable conditions,advantages and disadvantages are summarized and compared.Subsequently,the specific role of electrostatic interactions in governing the properties and behaviors of different complex fluids is emphasized and explained.Finally,challenges and perspective on the computational study of charged systems are given.展开更多
概述:老年抑郁症患者伴有躯体化症状在临床上非常常见。本病例报告了一例反复住院治疗,伴躯体症状的老年抑郁症患者。虽然在首次住院治疗获得了临床痊愈,但一年后病情复发,经过随访以及神经内科诊治,我们发现这其实是一例多系统萎缩(mul...概述:老年抑郁症患者伴有躯体化症状在临床上非常常见。本病例报告了一例反复住院治疗,伴躯体症状的老年抑郁症患者。虽然在首次住院治疗获得了临床痊愈,但一年后病情复发,经过随访以及神经内科诊治,我们发现这其实是一例多系统萎缩(multiple system atrophy,MSA)。这个病例的诊治过程提示我们对于一些反复治疗、疗效欠佳的老年抑郁症患者,尤其对于"躯体化症状"突出的病例,临床医生需要考虑是否存在躯体疾病,仔细寻找器质性病因。而快速动眼睡眠行为障碍(rapid eye movement sleep behavior disorder,RBD)展开更多
Recently,InE has been regarded as a popular education strategy in Chinese universities.However,problems have been exposed in the adoption of InE,for example,in InE courses and competitions.The purpose of this paper is...Recently,InE has been regarded as a popular education strategy in Chinese universities.However,problems have been exposed in the adoption of InE,for example,in InE courses and competitions.The purpose of this paper is to provide a possible solution to the problems,which is to organize effective InE courses by integrating InE with Inter-Course-level Problem-Based Learning(ICPBL).A detailed case is demonstrated by an ICPBL elective course design with deep integration of InE in the teaching,learning,and assessments.This paper contributes to a new curriculum design for promoting InE education in practically for Chinese universities.展开更多
The heat transfer of hydrocarbon refrigerant across tube bundles have been widely used in refrigeration.Three-dimensional simulation model using volume of fluid(VOF) was presented to study the effects of tube shapes o...The heat transfer of hydrocarbon refrigerant across tube bundles have been widely used in refrigeration.Three-dimensional simulation model using volume of fluid(VOF) was presented to study the effects of tube shapes on flow pattern, film thickness and heat transfer of n-pentane across tube bundles, including circle, ellipse-shaped, egg-shaped and cam-shaped tube bundles. Simulation results agree well with experimental data in the literature. The liquid film thickness of sheet flow and heat transfer for different tube shapes were obtained numerically. The flow pattern transition occurs lower vapor quality for ellipse-shaped tube than other tube shapes. For sheet flow, the liquid film on circle tube and ellipseshaped tube is symmetrically distributed along the circumferential direction. However, the liquid film on egg-shaped tube at circumferential angles(θ) = 15°–60° is thicker than θ = 135°–165°. The liquid film on cam tube at θ = 15°–60° is slightly thinner than θ = 135°–165°. The liquid film thickness varies from thinner to thicker for ellipse-shaped, cam-shaped, egg-shape and circle within θ = 15°–60°. The effect of tube shape is insignificant on thin liquid film thickness. Ellipse-shaped tube has largest heat transfer coefficient for sheet flow. In practical engineering, the tube shape could be designed as ellipse to promote heat transfer.展开更多
We have developed an electronic hardware system for the control and readout of multi-superconducting qubit devices.The hardware system is based on the design ideas of good scalability,high synchronization and low late...We have developed an electronic hardware system for the control and readout of multi-superconducting qubit devices.The hardware system is based on the design ideas of good scalability,high synchronization and low latency.The system,housed inside a VPX-6U chassis,includes multiple arbitrary-waveform generator(AWG)channels,analog-digital-converter(ADC)channels as well as direct current source channels.The system can be used for the control and readout of up to twelve superconducting transmon qubits in one chassis,and control and readout of more and more qubit can be carried out by interconnecting the chassis.By using field programmable gate array(FPGA)processors,the system incorporates three features that are specifically useful for superconducting qubit research.Firstly,qubit signals can be processed using the on-board FPGA after being acquired by ADCs,significantly reducing data processing time and data amount for storage and transmission.Secondly,different output modes,such as direct output and sequential output modes,of AWG can be implemented with pre-encoded FPGA.Thirdly,with data acquisition ADCs and control AWGs jointly controlled by the same FPGA,the feedback latency can be reduced,and in our test a 178.4 ns latency time is realized.This is very useful for future quantum feedback experiments.Finally,we demonstrate the functionality of the system by applying the system to the control and readout of a 10 qubit superconducting quantum processor.展开更多
Based on the Green Development Indicator System issued by the Chinese government, this study conducted an in-depth evaluation of provincial green development in China, from 2013 to 2016. The findings of the study show...Based on the Green Development Indicator System issued by the Chinese government, this study conducted an in-depth evaluation of provincial green development in China, from 2013 to 2016. The findings of the study showed that:(1) significant regional differences existed across provinces in China regarding green development.(2) In terms of changing trends, the overall level of green development exhibited an upward trend during the years covered by our study, with a faster rising rate of development in eastern and central regions of China than in western ones.(3) In terms of spatial correlation, the spatial autocorrelation of China’s green development was evident. However, the spatial agglomeration of provincial green development gradually waned during the period in 2013–2016.(4) When it comes to drivers of spatial autocorrelation, the comparatively upward trend in the environmental field served as the main factor that drove green development from agglomeration to balance.(5) In terms of convergence, the tendency showed that less developed regions were about to catch up with leading regions in China in green development, especially as regards the dimensions of ecological protection and resource utilization.展开更多
文摘Gastric cancer is one of the most common malignant tumors,for patients with advanced gastric cancer,the traditional treatment is mainly chemotherapy or combined targeted therapy;however,these have not achieved ideal efficacy.However,with the continuous deepening of research on molecular targeted drugs and immunosuppressants,the treatment of advanced gastric cancer patients has made new progress,and some new technologies have also been continuously emerged and applied,which brings hope for the treatment of advanced gastric cancer.Recently,several multicenter randomized controlled phase III studies on immunotherapy for advanced gastric cancer yielded encouraging results,demonstrating its superior efficacy in the treatment of advanced gastric cancer.However,prospective data to support the acceptance of surgery and the R0 removal rate following conversion therapy with immune checkpoint inhibitors are lacking.In this study,a 58-year-old woman with advanced gastric cancer and positive PD-L1 expression,negative HER-2 expression,and microsatellite stable status received immunochemotherapy combined with traditional Chinese medicine to achieve R0 resection and satisfactory efficacy.
文摘Aqueous ammonia(NH3) is a promising alternative solvent for the capture of industrial CO_2 emissions, given its high chemical stability and CO_2 removal capacity, and low material costs and regeneration energy. NH3 also has potential for capturing multiple flue gas components, including NOx, SOxand CO_2, and producing value-added chemicals. However, its high volatility and low reactivity towards CO_2 limit its economic viability. Considerable efforts have been made to advance aqueous NH3-based post-combustion capture technologies in the last few years: in particular, General Electric's chilled NH3 process, CSIRO's mild-temperature aqueous NH3 process and SRI International's mixed-salts(NH3 and potassium carbonate) technology. Here, we review these research activities and other developments in the field, and outline future research needed to further improve aqueous NH3-based CO_2 capture technologies.
基金Supported by Ministry of Industry and Information(No.K24097)
文摘The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low-speed model test. However, this method is problematic for ships with bulbous bows and transom. In this article, a Computational Fluid Dynamics(CFD)-based method is introduced to obtain k for different type of ships at different drafts, and a comparison is made between the CFD method and the model test. The results show that the CFD method produces reasonable k values. A grid generating method and turbulence model are briefly discussed in the context of obtaining a consistent k using CFD.
文摘Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the Haber-Bosch process.Unfortunately,the electrochemical N2 reduction reaction(NRR)method as a rising approach currently still shows low selectivity(Faradaic efficiency<10%)and high-energy consumption[applied potential at least-0.2 V versus the reversible hydrogen electrode(RHE)].Here,the role of molybdenum aluminum boride single crystals,belonging to a family of ternary transition metal aluminum borides known as MAB phases,is reported for the electrochemical NRR for the first time,at a low applied potential(-0.05 V versus RHE)under ambient conditions and in alkaline media.Due to the unique nano-laminated crystal structure of the MAB phase,these inexpensive materials have been found to exhibit excellent electrocatalytic performances(NH3 yield:9.2μg h^-1cm^-2mgcat^-1.,Faradaic efficiency:30.1%)at the low overpotential,and to display a high chemical stability and sustained catalytic performance.In conjunction,further mechanism studies indicate B and Al as main-group metals show a highly selective affinity to N2 due to the strong interaction between the B 2p/Al 3p band and the N 2p orbitals,while Mo exhibits specific catalytic activity toward the subsequent reduction reaction.Overall,the MAB-phase catalyst under the synergy of the elements within ternary compound can suppress the hydrogen evolution reaction and achieve enhanced NRR performance.The significance of this work is to provide a promising candidate in the future synthesis of ammonia.
基金supported by the National Natural Science Foundation of China(21776093,21376089,41976203,21506178,21908066)。
文摘Molecular simulation plays an increasingly important role in studying the properties of complex fluid systems containing charges,such as ions,piezoelectric materials,ionic liquids,ionic surfactants,polyelectrolytes,zwitterionic materials,nucleic acids,proteins,biomembranes and etc.,where the electrostatic interactions are of special significance.Several methods have been available for treating the electrostatic interactions in explicit and implicit solvent models.Accurate and efficient treatment of such interactions has therefore always been one of the most challenging issues in classical molecular dynamics simulations due to their inhomogeneity and long-range characteristics.Currently,two major challenges remain in the application field of electrostatic interactions in molecular simulations;(i)improving the representation of electrostatic interactions while reducing the computational costs in molecular simulations;(ii)revealing the role of electrostatic interactions in regulating the specific properties of complex fluids.In this review,the calculation methods of electrostatic interactions,including basic principles,applicable conditions,advantages and disadvantages are summarized and compared.Subsequently,the specific role of electrostatic interactions in governing the properties and behaviors of different complex fluids is emphasized and explained.Finally,challenges and perspective on the computational study of charged systems are given.
文摘概述:老年抑郁症患者伴有躯体化症状在临床上非常常见。本病例报告了一例反复住院治疗,伴躯体症状的老年抑郁症患者。虽然在首次住院治疗获得了临床痊愈,但一年后病情复发,经过随访以及神经内科诊治,我们发现这其实是一例多系统萎缩(multiple system atrophy,MSA)。这个病例的诊治过程提示我们对于一些反复治疗、疗效欠佳的老年抑郁症患者,尤其对于"躯体化症状"突出的病例,临床医生需要考虑是否存在躯体疾病,仔细寻找器质性病因。而快速动眼睡眠行为障碍(rapid eye movement sleep behavior disorder,RBD)
基金This research was financially supported by the PBL Research and Application Project of Northeastern University(Grant No.PBL-JX2021yb029,PBL-JX2021yb027).
文摘Recently,InE has been regarded as a popular education strategy in Chinese universities.However,problems have been exposed in the adoption of InE,for example,in InE courses and competitions.The purpose of this paper is to provide a possible solution to the problems,which is to organize effective InE courses by integrating InE with Inter-Course-level Problem-Based Learning(ICPBL).A detailed case is demonstrated by an ICPBL elective course design with deep integration of InE in the teaching,learning,and assessments.This paper contributes to a new curriculum design for promoting InE education in practically for Chinese universities.
基金supported by National Natural Science Foundation of China (52006242)National Natural Science Foundation of China (52192623)+1 种基金Science Foundation of China University of Petroleum,Beijing (ZX20200126)Science and technology program for strategic cooperation of CNPC–China University of Petroleum (ZLZX2020-05)。
文摘The heat transfer of hydrocarbon refrigerant across tube bundles have been widely used in refrigeration.Three-dimensional simulation model using volume of fluid(VOF) was presented to study the effects of tube shapes on flow pattern, film thickness and heat transfer of n-pentane across tube bundles, including circle, ellipse-shaped, egg-shaped and cam-shaped tube bundles. Simulation results agree well with experimental data in the literature. The liquid film thickness of sheet flow and heat transfer for different tube shapes were obtained numerically. The flow pattern transition occurs lower vapor quality for ellipse-shaped tube than other tube shapes. For sheet flow, the liquid film on circle tube and ellipseshaped tube is symmetrically distributed along the circumferential direction. However, the liquid film on egg-shaped tube at circumferential angles(θ) = 15°–60° is thicker than θ = 135°–165°. The liquid film on cam tube at θ = 15°–60° is slightly thinner than θ = 135°–165°. The liquid film thickness varies from thinner to thicker for ellipse-shaped, cam-shaped, egg-shape and circle within θ = 15°–60°. The effect of tube shape is insignificant on thin liquid film thickness. Ellipse-shaped tube has largest heat transfer coefficient for sheet flow. In practical engineering, the tube shape could be designed as ellipse to promote heat transfer.
基金Project supported by the State Key Development Program for Basic Research of China(Grants Nos.2017YFA0304300 and 2016YFA0300600)the Natural Science Foundation of Beijing,China(Grant No.Z190012)+1 种基金the Key-Area Research and Development Program of Guangdong Province,China(Grant No.2020B0303030001)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB28000000).
文摘We have developed an electronic hardware system for the control and readout of multi-superconducting qubit devices.The hardware system is based on the design ideas of good scalability,high synchronization and low latency.The system,housed inside a VPX-6U chassis,includes multiple arbitrary-waveform generator(AWG)channels,analog-digital-converter(ADC)channels as well as direct current source channels.The system can be used for the control and readout of up to twelve superconducting transmon qubits in one chassis,and control and readout of more and more qubit can be carried out by interconnecting the chassis.By using field programmable gate array(FPGA)processors,the system incorporates three features that are specifically useful for superconducting qubit research.Firstly,qubit signals can be processed using the on-board FPGA after being acquired by ADCs,significantly reducing data processing time and data amount for storage and transmission.Secondly,different output modes,such as direct output and sequential output modes,of AWG can be implemented with pre-encoded FPGA.Thirdly,with data acquisition ADCs and control AWGs jointly controlled by the same FPGA,the feedback latency can be reduced,and in our test a 178.4 ns latency time is realized.This is very useful for future quantum feedback experiments.Finally,we demonstrate the functionality of the system by applying the system to the control and readout of a 10 qubit superconducting quantum processor.
文摘Based on the Green Development Indicator System issued by the Chinese government, this study conducted an in-depth evaluation of provincial green development in China, from 2013 to 2016. The findings of the study showed that:(1) significant regional differences existed across provinces in China regarding green development.(2) In terms of changing trends, the overall level of green development exhibited an upward trend during the years covered by our study, with a faster rising rate of development in eastern and central regions of China than in western ones.(3) In terms of spatial correlation, the spatial autocorrelation of China’s green development was evident. However, the spatial agglomeration of provincial green development gradually waned during the period in 2013–2016.(4) When it comes to drivers of spatial autocorrelation, the comparatively upward trend in the environmental field served as the main factor that drove green development from agglomeration to balance.(5) In terms of convergence, the tendency showed that less developed regions were about to catch up with leading regions in China in green development, especially as regards the dimensions of ecological protection and resource utilization.
