期刊文献+
共找到199篇文章
< 1 2 10 >
每页显示 20 50 100
Post-acute ischemic stroke hyperglycemia aggravates destruction of the blood-brain barrier 被引量:1
1
作者 Tianqi Xu Jianhong Yang +5 位作者 Yao Xu Xiaofeng Wang Xiang Gao jie sun Chenhui Zhou Yi Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1344-1350,共7页
Post-acute ischemic stroke hyperglycemia increases the risk of hemorrhagic transformation,which is associated with blood-brain barrier disruption.Brain microvascular endothelial cells are a major component of the bloo... Post-acute ischemic stroke hyperglycemia increases the risk of hemorrhagic transformation,which is associated with blood-brain barrier disruption.Brain microvascular endothelial cells are a major component of the blood-brain barrier.Intercellular mitochondrial transfer has emerged as a novel paradigm for repairing cells with mitochondrial dysfunction.In this study,we first investigated whether mitochondrial transfer exists between brain microvascular endothelial cells,and then investigated the effects of post-acute ischemic stroke hyperglycemia on mitochondrial transfer between brain microvascular endothelial cells.We found that healthy brain microvascular endothelial cells can transfer intact mitochondria to oxygen glucose deprivation-injured brain microvascular endothelial cells.However,post-oxygen glucose deprivation hyperglycemia hindered mitochondrial transfer and exacerbated mitochondrial dysfunction.We established an in vitro brain microvascular endothelial cell model of the blood-brain barrier.We found that post-acute ischemic stroke hyperglycemia reduced the overall energy metabolism levels of brain microvascular endothelial cells and increased permeability of the blood-brain barrier.In a clinical study,we retrospectively analyzed the relationship between post-acute ischemic stroke hyperglycemia and the severity of hemorrhagic transformation.We found that post-acute ischemic stroke hyperglycemia serves as an independent predictor of severe hemorrhagic transformation.These findings suggest that post-acute ischemic stroke hyperglycemia can aggravate disruption of the blood-brain barrier by inhibiting mitochondrial transfer. 展开更多
关键词 acute ischemic stroke blood-brain barrier brain microvascular endothelial cells mitochondrial transfer stress hyperglycemia
下载PDF
Experimental study on the effect of unloading rate on gneiss rockburst 被引量:1
2
作者 Dongqiao Liu jie sun +4 位作者 Ran Li Manchao He Binghao Cao Chongyuan Zhang Wen Meng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2064-2076,共13页
Rockburst are often encountered in tunnel construction due to the complex geological conditions.To study the influence of unloading rate on rockburst,gneiss rockburst experiments were conducted under three groups of u... Rockburst are often encountered in tunnel construction due to the complex geological conditions.To study the influence of unloading rate on rockburst,gneiss rockburst experiments were conducted under three groups of unloading rates.A high-speed photography system and acoustic emission(AE)system were used to monitor the entire process of rockburst process in real-time.The results show that the intensity of gneiss rockburst decreases with decrease of unloading rate,which is manifested as the reduction of AE energy and fragments ejection velocity.The mechanisms are proposed to explain this effect:(i)The reduction of unloading rate changes the crack propagation mechanism in the process of rockburst.This makes the rockbursts change from the tensile failure mechanism at high unloading rate to the tension-shear mixed failure mechanism at low unloading rate,and more energy released in the form of shear crack propagation.Then,less strain energy is converted into kinetic energy of fragments ejection.(ii)Less plate cracking degree of gneiss has taken shape due to decrease of unloading rate,resulting in the destruction of rockburst incubation process.The enlightenments of reducing the unloading rate for the project are also described quantitatively.The rockburst magnitude is reduced from the medium magnitude at the unloading rate of 0.1 MPa/s to the slight magnitude at the unloading rate of 0.025 MPa/s,which was judged by the ejection velocity. 展开更多
关键词 ROCKBURST Unloading rate Crack propagation Influence mechanisms
下载PDF
Experimental study on the effect of water absorption level on rockburst occurrence of sandstone 被引量:1
3
作者 Dongqiao Liu jie sun +3 位作者 Pengfei He Manchao He Binghao Cao Yuanyuan Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期136-152,共17页
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ... To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation. 展开更多
关键词 ROCKBURST Water Prevention effect Crack evolution
下载PDF
探索依托单位科研管理新模式从源头提升科学基金资助效能——以山东大学为例
4
作者 胡大伟 孙婕 +2 位作者 毛毳 梁宗磊 郑学星 《中国科学基金》 CSCD 北大核心 2024年第1期211-216,共6页
当前,国家自然科学基金委员会正推进科学基金系统性改革,构建新时代科学基金体系,支撑国家高水平科技自立自强。依托单位作为科学基金体系的中坚力量,肩负着落实科学基金深化改革系列举措,践行高质量申请倡议,从源头上提升科学基金资助... 当前,国家自然科学基金委员会正推进科学基金系统性改革,构建新时代科学基金体系,支撑国家高水平科技自立自强。依托单位作为科学基金体系的中坚力量,肩负着落实科学基金深化改革系列举措,践行高质量申请倡议,从源头上提升科学基金资助效能的使命。本文以山东大学为例,简要介绍如何履行依托单位职责,发挥综合性大学独特的管理优势,从“学校—团队—个人”三个维度重构科研管理体系,创新科研组织管理模式,组建新型科研管理团队,提升项目科学问题质量,连续两年实现科学基金申请数量下降和获资助数量上升。 展开更多
关键词 科学基金 资助效能 依托单位 科研管理 申请质量
下载PDF
Monocyte and macrophage function in respiratory viral infections
5
作者 Mohd Arish jie sun 《Animal Diseases》 CAS 2024年第1期40-47,共8页
Pulmonary macrophages,such as tissue-resident alveolar and interstitial macrophages and recruited monocyte-derived macrophages,are the major macrophages present in the lungs during homeostasis and diseased conditions.... Pulmonary macrophages,such as tissue-resident alveolar and interstitial macrophages and recruited monocyte-derived macrophages,are the major macrophages present in the lungs during homeostasis and diseased conditions.While tissue-resident macrophages act as sentinels of the alveolar space and play an important role in maintaining homeostasis and immune regulation,recruited macrophages accumulate in the respiratory tract after acute viral infections.Despite sharing similar anatomical niches,these macrophages are distinct in terms of their origins,surface marker expression,and transcriptional profiles,which impart macrophages with distinguished characteristics in physi-ological and pathophysiological conditions.In this review,we summarize the current view on these macrophage populations,their shared functions,and what makes them distinct from each other in the context of homeostasis andrespiratoryviral infections. 展开更多
关键词 Alveolar macrophages Interstitial macrophages Monocytes derived macrophages Viral infection IAV RSV SARS-COV-2
下载PDF
Hydrogen-bonded organic framework modified separator for simultaneously enhancing the safety and electrochemical performance of Ni-rich lithium-ion battery
6
作者 Chengyu Han Yu Cao +9 位作者 Ming Yang Yuhan Wang Di Tang Shaojie Zhang Yiran Jia Yiming Zhang Hern Kim Fusheng Pan Zhongyi Jiang jie sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期72-78,共7页
Nickel-rich layered oxide cathode(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x>0.5,NCM)shows substantial potential for applications in longer-range electrical vehicles.However,the rapid capacity decay and serious safety concern... Nickel-rich layered oxide cathode(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x>0.5,NCM)shows substantial potential for applications in longer-range electrical vehicles.However,the rapid capacity decay and serious safety concerns impede its practical viability.This work provides a hydrogen-bonded organic framework(HOF)modification strategy to simultaneously improve the electrochemical performance,thermal stability and incombustibility of separator.Melamine cyanurate(MCA),as a low-cost and reliable flame-retardant HOF,was implemented in the separator modification layer,which can prevent the battery short circuit even at a high temperature.In addition,the supermolecule properties of MCA provide unique physical and chemical microenvironment for regulating ion-transport behavior in electrolyte.The MCA coating layer enabled the nickel-rich layered oxide cathode with a high-capacity retention of 90.3%after 300 cycles at 1.0 C.Collectively,the usage of MCA in lithium-ion batteries(LIBs)affords a simple,low-cost and efficient strategy to improve the security and service life of nickel-rich layered cathodes. 展开更多
关键词 Hydrogen-bonded organic framework Modified separator Ni-richlayered oxide cathode Thermal runaway Li^(+)transference number
下载PDF
High-Efficiency Photo-Induced Charge Transfer for SERS Sensing in N-Doped 3D-Graphene on Si Heterojunction
7
作者 Guanglin Zhang jie sun +10 位作者 Genwang Wei Shan Zhang Zhengyi He Huijuan Wu Bingkun Wang Siwei Yang Guqiao Ding Zhiduo Liu Zhiwen Jin Caichao Ye Gang Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期268-276,共9页
Nitrogen-doped three-dimensional graphene(N-doped 3D-graphene)is a graphene derivative with excellent adsorption capacity,large specific surface area,high porosity,and optoelectronic properties.Herein,N-doped 3D-graph... Nitrogen-doped three-dimensional graphene(N-doped 3D-graphene)is a graphene derivative with excellent adsorption capacity,large specific surface area,high porosity,and optoelectronic properties.Herein,N-doped 3D-graphene/Si heterojunctions were grown in situ directly on silicon(Si)substrates via plasma-assisted chemical vapor deposition(PACVD),which is promising for surface-enhanced Raman scattering(SERS)substrates candidates.Combined analyses of theoretical simulation,incorporating N atoms in 3D-graphene are beneficial to increase the electronic state density of the system and enhance the charge transfer between the substrate and the target molecules.The enhancement of the optical and electric fields benefits from the stronger light-matter interaction improved by the natural nano-resonator structure of N-doped 3D-graphene.The as-prepared SERS substrates based on N-doped 3D-graphene/Si heterojunctions achieve ultra-low detection for various molecules:10^(-8)M for methylene blue(MB)and 10^(-9)M for crystal violet(CRV)with rhodamine(R6G)of 10^(10)M.In practical detected,10^(-8)M thiram was precisely detected in apple peel extract.The results indicate that N-doped 3D-graphene/Si heterojunctions based-SERS substrates have promising applications in low-concentration molecular detection and food safety. 展开更多
关键词 charge transfer DFT simulation N-doped 3D-graphene SERS Thiram detection
下载PDF
Hybrid HMX multi-level assembled under the constraint of 2D materials with efficiently reduced sensitivity and optimized thermal stability
8
作者 Xiaomin Song Longjin Huang +3 位作者 Rufang Peng Qi Huang Jinjiang Xu jie sun 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期123-132,共10页
The interfacial interaction between HMX molecules and coating materials is the key to the safety performance of explosives and has received extensive attention.However,screening suitable coating agents to enhance the ... The interfacial interaction between HMX molecules and coating materials is the key to the safety performance of explosives and has received extensive attention.However,screening suitable coating agents to enhance the interfacial effect to obtain high-energy and low-sensitivity explosives has long been a major challenge.In this work,HMX-PEI/rGO/g-C_(3)N_(4)(HPrGC)composites were innovatively prepared by a multi-level coating strategy of two-dimensional graphite rGO and g-C_(3)N_(4).The g-C_(3)N_(4) used for desensitization has a richπ-conjugated system and shows outstanding ability in reducing friction sensitivity.The hierarchical structure of HPrGC formed by electrostatic self-assembly andπ-πstacking can effectively dissipate energy accumulation under heat and mechanical stimulation through structural evolution,thus exhibiting a prominent synergistic desensitization effect on HMX.The results show that rGO/gC_(3)N_(4) coating has no effect on the crystal structure and chemical structure of HMX.More importantly,the perfect combination of g-C_(3)N_(4) and rGO endows HPrGC with enhanced thermal stability and ideal mechanical sensitivity(IS:21 J,FS:216 N).Obviously,the new fabrication of HPrGC enriches the variety of desensitizer materials and helps to deepen the understanding of the interaction between explosives and coatings. 展开更多
关键词 HMX-PEI/rGO/g-C_(3)N_(4) Electrostatic self-assembly π-πstacking Synergistic desensitization
下载PDF
A Quasi-Linear Relationship between Planetary Outgoing Longwave Radiation and Surface Temperature in a Radiative-Convective-Transportive Climate Model of a Gray Atmosphere
9
作者 jie sun Michael SECOR +1 位作者 Ming CAI Xiaoming HU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期8-18,共11页
In this study,we put forward a radiative-convective-transportive energy balance model of a gray atmosphere to examine individual roles of the greenhouse effect of water vapor,vertical convection,and atmospheric polewa... In this study,we put forward a radiative-convective-transportive energy balance model of a gray atmosphere to examine individual roles of the greenhouse effect of water vapor,vertical convection,and atmospheric poleward energy transport as well as their combined effects for a quasi-linear relationship between the outgoing longwave radiation(OLR)and surface temperature(T_(S)).The greenhouse effect of water vapor enhances the meridional gradient of surface temperature,thereby directly contributing to a quasi-linear OLR-T_(S) relationship.The atmospheric poleward energy transport decreases the meridional gradient of surface temperature.As a result of the poleward energy transport,tropical(high-latitude)atmosphere-surface columns emit less(more)OLR than the solar energy input at their respective locations,causing a substantial reduction of the meridional gradient of the OLR.The combined effect of reducing the meridional gradients of both OLR and surface temperature by the poleward energy transport also contributes to the quasi-linear OLR-T_(S) relationship.Vertical convective energy transport reduces the meridional gradient of surface temperature without affecting the meridional gradient of OLR,thereby suppressing part of the reduction to the increasing rate of OLR with surface temperature by the greenhouse effect of water vapor and poleward energy transport.Because of the nature of the energy balance in the climate system,such a quasi-linear relationship is also a good approximation for the relationship between the annual-mean net downward solar energy flux at the top of the atmosphere and surface temperature. 展开更多
关键词 outgoing longwave radiation greenhouse effect poleward energy transport
下载PDF
Three-dimensional printing for preoperative rehearsal and intraoperative navigation during laparoscopic rectal cancer surgery with left colic artery preservation
10
作者 Zong-Xian Zhao Zong-Ju Hu +4 位作者 Run-Dong Yao Xin-Yu Su Shu Zhu jie sun Yuan Yao 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3104-3113,共10页
BACKGROUND Prior studies have shown that preserving the left colic artery(LCA)during laparo-scopic radical resection for rectal cancer(RC)can reduce the occurrence of anasto-motic leakage(AL),without compromising onco... BACKGROUND Prior studies have shown that preserving the left colic artery(LCA)during laparo-scopic radical resection for rectal cancer(RC)can reduce the occurrence of anasto-motic leakage(AL),without compromising oncological outcomes.However,anatomical variations in the branches of the inferior mesenteric artery(IMA)and LCA present significant surgical challenges.In this study,we present our novel three dimensional(3D)printed IMA model designed to facilitate preoperative rehearsal and intraoperative navigation to analyze its impact on surgical safety.AIM To investigate the effect of 3D IMA models on preserving the LCA during RC surgery.METHODS We retrospectively collected clinical dates from patients with RC who underwent laparoscopic radical resection from January 2022 to May 2024 at Fuyang People’s Hospital.Patients were divided into the 3D printing and control groups for sta-tistical analysis of perioperative characteristics.RESULTS The 3D printing observation group comprised of 72 patients,while the control group comprised 68 patients.The operation time(174.5±38.2 minutes vs 198.5±49.6 minutes,P=0.002),intraoperative blood loss(43.9±31.3 mL vs 58.2±30.8 mL,P=0.005),duration of hospitalization(13.1±3.1 days vs 15.9±5.6 days,P<0.001),postoperative recovery time(8.6±2.6 days vs 10.5±4.9 days,P=0.007),and the postoperative complication rate(P<0.05)were all significantly lower in the observation group.CONCLUSION Utilization of a 3D-printed IMA model in laparoscopic radical resection of RC can assist surgeons in understanding the LCA anatomy preoperatively,thereby reducing intraoperative bleeding and shortening operating time,demonstrating better clinical application potential. 展开更多
关键词 Rectal cancer Three-dimensional printing Inferior mesenteric artery Left colic artery Preoperative rehearsal Intraoperative navigation
下载PDF
DNA损伤修复基因胚系突变乳腺癌新辅助化疗疗效分析 被引量:5
11
作者 刘婧思 陈久安 +4 位作者 孙洁 姚璐 张娟 解云涛 徐晔 《中国肿瘤临床》 CAS CSCD 北大核心 2023年第10期497-503,共7页
目的:分析携带DNA损伤修复(DNA damage repair,DDR)相关基因突变的乳腺癌患者对基础蒽环类新辅助化疗方案(anthracycline,A)、蒽环联合紫杉类新辅助化疗方案(anthracycline-taxane,A-T)、蒽环联合紫杉和铂类新辅助化疗方案(anthracyclin... 目的:分析携带DNA损伤修复(DNA damage repair,DDR)相关基因突变的乳腺癌患者对基础蒽环类新辅助化疗方案(anthracycline,A)、蒽环联合紫杉类新辅助化疗方案(anthracycline-taxane,A-T)、蒽环联合紫杉和铂类新辅助化疗方案(anthracycline-taxane/carboplatin,A-TP)的疗效反应。方法:2003年10月至2015年5月,105例携带DDR基因胚系突变(非BRCA)的原发性乳腺癌患者在北京大学肿瘤医院分别接受A(n=69)、A-T(n=19)、A-TP(n=17)3种新辅助化疗方案。通过χ2检验或Fisher精确检验比较3组患者的病理完全缓解(pathological complete remission,pCR)率;采用Kaplan-Meier生存分析和Cox回归模型分析患者的乳腺癌特异生存(breast cancer-specific survival,BCSS)及无复发生存(recurrence-free survival,RFS)。结果:93.3%(98/105)的患者接受了4~8个周期的新辅助化疗。接受A、A-T、A-TP新辅助方案的3组患者的pCR率分别为11.6%、21.1%和35.3%。A-TP组pCR率显著高于A组(P=0.028),A-TP组pCR率也高于A-T组,但未达到统计学差异。经过65.6个月的中位随访,A-TP组的BCSS(HR=0.50,95%CI:0.09~2.73,P=0.41)和RFS(HR=0.51,95%CI:0.15~1.74,P=0.27)略优于A-T组,但无统计学差异。结论:DDR基因胚系突变患者应用A-TP新辅助化疗方案可显著提高pCR率,加入铂类药物或可提高患者的药物反应性及预后。 展开更多
关键词 乳腺癌 DNA 损伤修复基因 新辅助化疗 病理完全缓解
下载PDF
高等教育质量提升的“增长绩效” 被引量:1
12
作者 李子联 孙杰 张艳 《教育与经济》 北大核心 2023年第6期60-68,共9页
通过测算宏观层面的高等教育质量指数,对全国和地区样本内高等教育质量提升所带来的“增长绩效”进行了综合检验。研究发现:首先,高等教育质量提升对经济增长带来了“直接效应”,即高校扩招以来虽然我国高等教育质量的提升幅度总体较小... 通过测算宏观层面的高等教育质量指数,对全国和地区样本内高等教育质量提升所带来的“增长绩效”进行了综合检验。研究发现:首先,高等教育质量提升对经济增长带来了“直接效应”,即高校扩招以来虽然我国高等教育质量的提升幅度总体较小,但却不可忽视其在经济高速增长中的重要作用。其次,高等教育质量提升对经济增长带来了“间接效应”,即高等教育质量提升通过促进科技创新而间接地带来了社会总产出的增加。最后,在吸收外地高等教育质量提升对本土增长绩效的外溢作用的力度上,“直接效应”在东部地区最强,中部和西部地区则不显著;“间接效应”在东部和中部地区均为正,而在西部地区则为负,这与“西北有高楼”和“孔雀东南飞”的要素流向现实极为吻合。 展开更多
关键词 高等教育质量 增长绩效 直接效应 间接效应 外溢效应
下载PDF
Advances in the Application of Perovskite Materials 被引量:6
13
作者 Lixiu Zhang Luyao Mei +37 位作者 Kaiyang Wang Yinhua Lv Shuai Zhang Yaxiao Lian Xiaoke Liu Zhiwei Ma Guanjun Xiao Qiang Liu Shuaibo Zhai Shengli Zhang Gengling Liu Ligang Yuan Bingbing Guo Ziming Chen Keyu Wei Aqiang Liu Shizhong Yue Guangda Niu Xiyan Pan jie sun Yong Hua Wu‑Qiang Wu Dawei Di Baodan Zhao Jianjun Tian Zhijie Wang Yang Yang Liang Chu Mingjian Yuan Haibo Zeng Hin‑Lap Yip Keyou Yan Wentao Xu Lu Zhu Wenhua Zhang Guichuan Xing Feng Gao Liming Ding 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期334-381,共48页
Nowadays, the soar of photovoltaic performance of perovskite solar cells has set off a fever in the study of metal halide perovskite materials. The excellent optoelectronic properties and defect tolerance feature allo... Nowadays, the soar of photovoltaic performance of perovskite solar cells has set off a fever in the study of metal halide perovskite materials. The excellent optoelectronic properties and defect tolerance feature allow metal halide perovskite to be employed in a wide variety of applications. This article provides a holistic review over the current progress and future prospects of metal halide perovskite materials in representative promising applications, including traditional optoelectronic devices(solar cells, light-emitting diodes, photodetectors, lasers), and cutting-edge technologies in terms of neuromorphic devices(artificial synapses and memristors) and pressure-induced emission. This review highlights the fundamentals, the current progress and the remaining challenges for each application, aiming to provide a comprehensive overview of the development status and a navigation of future research for metal halide perovskite materials and devices. 展开更多
关键词 Perovskites Optoelectronic devices Neuromorphic devices Pressure-induced emission
下载PDF
Effects of mixed fertilizers formed by the compounding of two targeted controlled-release nitrogen fertilizers on yield,nitrogen use efficiency,and ammonia volatilization in double-cropping rice 被引量:2
14
作者 Jian Ke jie sun +7 位作者 Tingting Chen Shibao Tao Tiezhong Zhu Chuanjun Yin Haibing He Cuicui You Liquan Wu Shuangshuang Guo 《The Crop Journal》 SCIE CSCD 2023年第2期628-637,共10页
One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and fro... One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and from PI to heading(HS)is expected to synchronize the double-peak N demand of rice.However,its effects on the yield and N use efficiency(NUE)of labor-intensive double-cropping rice were unknown.Two targeted CRU(CRU_(A)and CRU_(B))were compounded in five ratios(CRU_(A):CRU_(B)=10:0,7:3,5:5,3:7,and 0:10)to form five mixed fertilizers(BBFs):BBF1-5.A field experiment was performed to investigate the characteristics of N supply in early and late seasons under different BBFs and their effects on N uptake,yield,and ammonia volatilization(AV)loss from paddy fields of double-cropping rice.Conventional high-yield fertilization(CK,three split applications of urea)and zero-N treatments were established as controls.The N supply dropped significantly with the increased compound ratio of CRU_(B)during the period from TS to PI,but increased during the period from PI to HS.With the exception of the period from TS to PI in the late rice season,the N uptake of early and late rice maintained close synchronicity with the N supply of BBFs during the double-peak periods.Excessive N supply(BBF1 and BBF2)in the late rice season during the period from TS to PI increased N loss by AV.The effect of BBF on grain yield increase varied widely between seasons,irrespective of year.Among the BBFs,the BBF2 treatment of early rice not only stabilized the spikelets per panicle but also ensured a high number of effective panicles by promoting N uptake during the period from TS to PI and a high grain-filling percentage by appropriately reducing the N supply at the later PI stage,resulting in the highest rice yield.While stabilizing the effective panicle number,the BBF4 treatment of late rice increased the number of spikelets per panicle by promoting N uptake during the period from PI to HS,resulting in the highest rice yield.The two-year average yield and apparent N recovery efficiency of the BBF2 treatment during the early rice season were 9.6 t ha 1 and 45.3%,while those of late rice in BBF4 were 9.6 t ha 1 and 43.0%,respectively.The yield and NUE indexes of BBF2 in early rice and BBF4 in late rice showed no significant difference from those of CK.The AVs of BBF2 during the early rice season and of BBF4 during the late rice season were 50.0%and 76.8%lower,respectively,than those of CK.BBF2 and BBF4 could effectively replace conventional urea split fertilization in early and late rice seasons,ensuring rice yield and NUE and reducing AV loss in paddy fields. 展开更多
关键词 Targeted controlled-release fertilizer Mixed fertilizer Double-cropping rice N uptake YIELD
下载PDF
Sediment Erosion on Pelton Turbines:A Review 被引量:1
15
作者 Xinfeng Ge jie sun +8 位作者 Dongdong Chu Juan Liu Ye Zhou Hui Zhang Lei Zhang Huixiang Chen Kan Kan Maxime Binama Yuan Zheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期36-62,共27页
The Pelton turbine has been widely used to develop high-head water resources with sediments because of its advantages in life cycle costs.When a flood or monsoon season occurs,the sediment concentration in the river i... The Pelton turbine has been widely used to develop high-head water resources with sediments because of its advantages in life cycle costs.When a flood or monsoon season occurs,the sediment concentration in the river increases suddenly,causing severe erosion to the nozzle,needle,and runner of Pelton turbines.After decades of development,researchers have developed practical engineering experience to reduce the sediment concentration of the flow through the turbine and ensure the safety and efficiency of power generation.Research on the mechanism of sediment erosion,development of anti-erosion materials,and establishment of erosion prediction models have attracted scholarly interest in recent years.Extensive research has been conducted to determine a complete and valuable syndication erosion model.However,owing to the complexity of the flow and wear mechanisms,the influence of specific parameters of erosion and the syndication effect is still difficult to determine.Computational fluid dynamics and erosion monitoring technology have also been evaluated and applied.This paper presents a comprehensive review of the erosion of Pelton turbines,some of the latest technical methods,and possible future development directions. 展开更多
关键词 Pelton turbine Sediment erosion Sediment erosion mechanism CFD The experimental method
下载PDF
Construction of clinical research nurse training program based on position competence 被引量:2
16
作者 jie sun Wen-Chuan Shan +4 位作者 Jun-Mei Liu Qin-Qin Zhang Yi Ye Shu-Ting Huang Keng Zhong 《World Journal of Clinical Cases》 SCIE 2023年第30期7363-7371,共9页
BACKGROUND As one of the most important members in clinical trials,the number of clinical research nurses(CRN)can't keep up with the growth of experimental projects,so it is urgent to build clinical research train... BACKGROUND As one of the most important members in clinical trials,the number of clinical research nurses(CRN)can't keep up with the growth of experimental projects,so it is urgent to build clinical research training and strengthen the background knowledge of nurses.AIM To construct CRN training program based on position competence,accelerate the construction of CRN talent pool,and provide scientific guidance significance for CRN training.METHODS Based on the position competence model,combined with literature research and qualitative interview results,the first draft was prepared of the CRN training program.Two rounds of correspondence with 16 experts were conducted using the Delphi method to determine the training program.RESULTS The effective recovery rate of the expert correspondence questionnaire was 100%and the authority coefficients of the 2 rounds of experts were 0.826 and 0.895.Finally,4 first-level indicators and determine 15 s-level indicators of training objectives.The training program included 4 first-level indicators,training requirements,content,methods,assessment and evaluation,15 s-level indicators,and 74 third-level indicators.CONCLUSION The CRN training program based on position competence is scientific and extendable,providing a basis for participation in CRN training. 展开更多
关键词 Research nurses Position competence Training program Delphi method
下载PDF
Siamese Dense Pixel-Level Fusion Network for Real-Time UAV Tracking 被引量:1
17
作者 Zhenyu Huang Gun Li +4 位作者 Xudong sun Yong Chen jie sun Zhangsong Ni Yang Yang 《Computers, Materials & Continua》 SCIE EI 2023年第9期3219-3238,共20页
Onboard visual object tracking in unmanned aerial vehicles(UAVs)has attractedmuch interest due to its versatility.Meanwhile,due to high precision,Siamese networks are becoming hot spots in visual object tracking.Howev... Onboard visual object tracking in unmanned aerial vehicles(UAVs)has attractedmuch interest due to its versatility.Meanwhile,due to high precision,Siamese networks are becoming hot spots in visual object tracking.However,most Siamese trackers fail to balance the tracking accuracy and time within onboard limited computational resources of UAVs.To meet the tracking precision and real-time requirements,this paper proposes a Siamese dense pixel-level network for UAV object tracking named SiamDPL.Specifically,the Siamese network extracts features of the search region and the template region through a parameter-shared backbone network,then performs correlationmatching to obtain the candidate regionwith high similarity.To improve the matching effect of template and search features,this paper designs a dense pixel-level feature fusion module to enhance the matching ability by pixel-wise correlation and enrich the feature diversity by dense connection.An attention module composed of self-attention and channel attention is introduced to learn global context information and selectively emphasize the target feature region in the spatial and channel dimensions.In addition,a target localization module is designed to improve target location accuracy.Compared with other advanced trackers,experiments on two public benchmarks,which are UAV123@10fps and UAV20L fromthe unmanned air vehicle123(UAV123)dataset,show that SiamDPL can achieve superior performance and low complexity with a running speed of 100.1 fps on NVIDIA TITAN RTX. 展开更多
关键词 Siamese network UAV object tracking dense pixel-level feature fusion attention module target localization
下载PDF
Linearly Polarization-Sensitive Perovskite Photodetectors 被引量:1
18
作者 jie sun Liming Ding 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第6期428-435,共8页
Polarization means symmetry loss for light vibration along light propagation direction,which is a particular physical property of light.The polarization state is indecipherable for most polarization-insensitive detect... Polarization means symmetry loss for light vibration along light propagation direction,which is a particular physical property of light.The polarization state is indecipherable for most polarization-insensitive detectors.Polarization can carry and differentiate light information,and can be used in polarized light detection,polarization imaging and encryption communication[1].Photodetectors are the core component of some photoelectric devices[2]used in biomedical sensing,remote sensing,military field,etc. 展开更多
关键词 Polarization SYMMETRY POLARIZED
下载PDF
Managing excess PbI_(2)for efficient perovskite solar cells 被引量:1
19
作者 Xiaodong Li jie sun +2 位作者 Bozhang Li Junfeng Fang Liming Ding 《Journal of Semiconductors》 EI CAS CSCD 2023年第8期7-9,共3页
Perovskite solar cells(PSCs)have attracted much attention due to their low cost,high efficiency and easy processing.Recently,You et al.achieved a record efficiency of 26.1%(certified 25.6%)in PSCs with excellent stabi... Perovskite solar cells(PSCs)have attracted much attention due to their low cost,high efficiency and easy processing.Recently,You et al.achieved a record efficiency of 26.1%(certified 25.6%)in PSCs with excellent stability[1].Excess PbI_(2) in perovskite films was converted into inactive(PbI_(2))2RbCl to avoid its detrimental effect to device stability,while maintaining its positive effect to device efficiency. 展开更多
关键词 PEROVSKITE STABILITY EXCESS
下载PDF
Cancer risk in relatives of BRCA1/2 pathogenic variant carriers in a large series of unselected patients with breast cancer
20
作者 Jiaming Liu Lu Yao +5 位作者 jie sun Li Hu Jiuan Chen Juan Zhang Ye Xu Yuntao Xie 《Cancer Biology & Medicine》 SCIE CAS CSCD 2023年第2期147-154,共8页
Objective:The spectrum and risk of cancer in relatives of BRCA1/2 pathogenic variant carriers in the Chinese population have not been established.Methods:A family history of cancer in 9903 unselected breast cancer pat... Objective:The spectrum and risk of cancer in relatives of BRCA1/2 pathogenic variant carriers in the Chinese population have not been established.Methods:A family history of cancer in 9903 unselected breast cancer patients was retrospectively analyzed.BRCA1/2 status was determined for all patients and relative risks(RRs)were calculated to evaluate cancer risk in relatives of the patients.Results:The incidences of breast cancer in female relatives of BRCA1 carriers,BRCA2 carriers,and non-carriers were 33.0%,32.2%,and 7.7%,respectively.The corresponding incidences of ovarian cancer were 11.5%,2.4%,and 0.5%,respectively.The incidences of pancreatic cancer in male relatives of BRCA1 carriers,BRCA2 carriers,and non-carriers were 1.4%,2.7%,and 0.6%,respectively.The corresponding incidences of prostate cancer were 1.0%,2.1%,and 0.4%,respectively.The risks of breast and ovarian cancers in female relatives of BRCA1 and BRCA2 carriers were significantly higher than female relatives of non-carriers(BRCA1:RR=4.29,P<0.001 and RR=21.95,P<0.001;BRCA2:RR=4.19,P<0.001 and RR=4.65,P<0.001,respectively).Additionally,higher risks of pancreatic and prostate cancers were noted in male relatives of BRCA2 carriers than non-carriers(RR=4.34,P=0.001 and RR=4.86,P=0.001,respectively).Conclusions:Female relatives of BRCA1 and BRCA2 carriers are at increased risk for breast and ovarian cancers,and male relatives of BRCA2 carriers are at increased risk for pancreatic and prostate cancers. 展开更多
关键词 BRCA1 variant BRCA2 variant cancer risk in relatives Chinese breast cancer patients family history of cancer
下载PDF
上一页 1 2 10 下一页 到第
使用帮助 返回顶部