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Outcomes of endoscopic sclerotherapy for jejunal varices at the site of choledochojejunostomy (with video): Three case reports 被引量:1
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作者 jun liu Peng Wang +2 位作者 Li-Mei Wang Jing Guo Ning Zhong 《World Journal of Gastroenterology》 SCIE CAS 2024年第14期2059-2067,共9页
BACKGROUND Hemorrhage associated with varices at the site of choledochojejunostomy is an unusual,difficult to treat,and often fatal manifestation of portal hypertension.So far,no treatment guidelines have been establi... BACKGROUND Hemorrhage associated with varices at the site of choledochojejunostomy is an unusual,difficult to treat,and often fatal manifestation of portal hypertension.So far,no treatment guidelines have been established.CASE SUMMARY We reported three patients with jejunal varices at the site of choledochojejun-ostomy managed by endoscopic sclerotherapy with lauromacrogol/α-butyl cyanoacrylate injection at our institution between June 2021 and August 2023.We reviewed all patient records,clinical presentation,endoscopic findings and treatment,outcomes and follow-up.Three patients who underwent pancre-aticoduodenectomy with a Whipple anastomosis were examined using conven-tional upper gastrointestinal endoscopy for suspected hemorrhage from the afferent jejunal loop.Varices with stigmata of recent hemorrhage or active he-morrhage were observed around the choledochojejunostomy site in all three patients.Endoscopic injection of lauromacrogol/α-butyl cyanoacrylate was carried out at jejunal varices for all three patients.The bleeding ceased and patency was observed for 26 and 2 months in two patients.In one patient with multiorgan failure and internal environment disturbance,rebleeding occurred 1 month after endoscopic sclerotherapy,and despite a second endoscopic sclero-therapy,repeated episodes of bleeding and multiorgan failure resulted in eventual death.CONCLUSION We conclude that endoscopic sclerotherapy with lauromacrogol/α-butyl cyanoac-rylate injection can be an easy,effective,safe and low-cost treatment option for jejunal varicose bleeding at the site of choledochojejunostomy. 展开更多
关键词 Endoscopic sclerotherapy Jejunal varices CHOLEDOCHOJEJUNOSTOMY Portal vein hypertension Case report
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Real-Time Monitoring of Meteorological Data at In-Situ GCW Remediation Sites
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作者 Qinghai Wu Xiaofeng Yang +2 位作者 jun liu Ruiqi Wang Quanyou Fu 《Journal of Geoscience and Environment Protection》 2024年第9期152-166,共15页
To optimize the self-organization network, self-adaptation, real-time monitoring, remote management capability, and equipment reuse level of the meteorological station supporting the portable groundwater circulation w... To optimize the self-organization network, self-adaptation, real-time monitoring, remote management capability, and equipment reuse level of the meteorological station supporting the portable groundwater circulation wells, and to provide real-time and effective technical services and environmental data support for groundwater remediation, a real-time monitoring system design of the meteorological station supporting the portable groundwater circulation wells based on the existing equipment is proposed. A variety of environmental element information is collected and transmitted to the embedded web server by the intelligent weather transmitter, and then processed by the algorithm and stored internally, displayed locally, and published on the web. The system monitoring algorithm and user interface are designed in the CNWSCADA development environment to realize real-time processing and analysis of environmental data and monitoring, control, management, and maintenance of the system status. The PLC-controlled photovoltaic power generating panels and lithium battery packs are in line with the concept of energy saving and emission reduction, and at the same time, as an emergency power supply to guarantee the safety of equipment and data when the utility power fails to meet the requirements. The experiment proves that the system has the characteristics of remote control, real-time interaction, simple station deployment, reliable operation, convenient maintenance, and green environment protection, which is conducive to improving the comprehensive utilization efficiency of various types of environmental information and providing reliable data support, theoretical basis and guidance suggestions for the research of groundwater remediation technology and its disciplines, and the research and development of the movable groundwater cycling well monitoring system. 展开更多
关键词 Groundwater Circulation Well Weather Station Real-Time Monitoring Embedded Web Server
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生成式人工智能的教育应用监管路线图——UNESCO《教育和研究领域生成式人工智能使用指南》解读与启示 被引量:1
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作者 刘军 雷亮 +1 位作者 钟昌振 熊立春 《中国教育信息化》 2024年第8期13-28,共16页
随着以ChatGPT为代表的生成式人工智能的问世及快速迭代,生成式人工智能对教育和研究产生巨大的促进作用,同时也带来前所未有的风险和挑战。2023年9月7日,联合国教科文组织发布首部关于生成式人工智能应用的全球指导性文件——《教育和... 随着以ChatGPT为代表的生成式人工智能的问世及快速迭代,生成式人工智能对教育和研究产生巨大的促进作用,同时也带来前所未有的风险和挑战。2023年9月7日,联合国教科文组织发布首部关于生成式人工智能应用的全球指导性文件——《教育和研究领域生成式人工智能使用指南》。通过对该指南的文本分析,介绍文件的出台背景和内容梗概,讨论生成式人工智能所引发的争议和负面影响,呈现了教育和研究领域使用生成式人工智能的监管框架,绘制生成式人工智能在教育和研究领域的应用监管“路线图”,最后结合生成式人工智能在我国教育和研究中的使用现状,向政府部门、科技公司、学校等教育机构、教师、研究人员、学生分别提出相关建议:政府部门要完善政策框架,加强公众参与;科技公司要坚持以人为本,维护数字正义;学校等教育机构要优化校本政策,重塑学习环境,开展AI培训;教师要变革教学方式,开展人机合作,进行伦理示范;研究人员要拓展研究领域,提升研究效能;学生要合理使用工具,强化传统技能。 展开更多
关键词 联合国教科文组织 生成式人工智能 教育和研究 指南 监管 路线图
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基于Y-SNP和Y-STR揭示汉族人群父系遗传关系
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作者 朱信 金鑫 +5 位作者 刘俊 杨澜 邹丽馨 李彩霞 黄江 江丽 《遗传》 CAS CSCD 北大核心 2024年第2期149-167,共19页
汉族是中国人口最多的民族,现有研究多集中于汉族人群的起源、迁徙、融合等遗传历史,以及局部地区汉族人群的父系遗传关系,鲜有全局视角下的汉族人群父系遗传结构研究。本研究检测了362份青海、四川和辽宁的汉族无关男性样本,整合已发... 汉族是中国人口最多的民族,现有研究多集中于汉族人群的起源、迁徙、融合等遗传历史,以及局部地区汉族人群的父系遗传关系,鲜有全局视角下的汉族人群父系遗传结构研究。本研究检测了362份青海、四川和辽宁的汉族无关男性样本,整合已发表文献相关数据,最终获得了国内15个省份16个汉族人群1830人份样本,覆盖89个Y-SNP、16个Y-STR的数据。通过统计Y-SNP单倍群频率、Y-STR单倍型多样性,使用主成分分析(principal component analysis,PCA)、系统发育树、单倍型网络等分析,综合Y-SNP和Y-STR两个反映不同时间尺度的遗传标记,研究不同地区汉族人群之间的遗传分化、汉族人群与其周边少数民族的遗传关系。单倍群频率统计结果显示单倍群O-M175是汉族人群主体单倍群(青海汉族60.53%~广东汉族92.7%),其下游亚单倍群呈现地域差异化分布。单倍群O2-M122高频分布于各地汉族,总体分布趋势北高南低;单倍群O1b-M268分布频率由南向北递减,尤其在岭南地区汉族人群中分布显著;单倍群O1a-M119在中部汉族人群中分布频率较高。汉族人群遗传结构研究表明,其主要分为北部、中部及南部三个聚类簇,其中青海汉族与其他地区汉族存在一定的遗传分化。在合并少数民族的遗传关系研究中,汉族人群彼此之间遗传关系更紧密,但北部汉族与回族遗传关系更近,而南部汉族则与仡佬族、黎族遗传关系更近。总之,本文基于89个Y-SNP和16个Y-STR,系统地研究了中国不同地域的汉族人群的单倍群分布、遗传亚结构及其与周边少数民族的遗传关系,为群体遗传学、法医遗传学补充理论依据,为Y染色体的法医学应用提供数据支撑。Y-SNP单倍群结合Y-STR单倍型对于分析汉族人群遗传亚结构以及法医学应用具有重要作用。 展开更多
关键词 群体遗传学 法医遗传学 Y-SNP Y-STR
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The Roadmap of 2D Materials and Devices Toward Chips 被引量:4
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作者 Anhan liu Xiaowei Zhang +16 位作者 Ziyu liu Yuning Li Xueyang Peng Xin Li Yue Qin Chen Hu Yanqing Qiu Han Jiang Yang Wang Yifan Li jun Tang jun liu Hao Guo Tao Deng Songang Peng He Tian Tian‑Ling Ren 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期343-438,共96页
Due to the constraints imposed by physical effects and performance degra certain limitations in sustaining the advancement of Moore’s law.Two-dimensional(2D)materials have emerged as highly promising candidates for t... Due to the constraints imposed by physical effects and performance degra certain limitations in sustaining the advancement of Moore’s law.Two-dimensional(2D)materials have emerged as highly promising candidates for the post-Moore era,offering significant potential in domains such as integrated circuits and next-generation computing.Here,in this review,the progress of 2D semiconductors in process engineering and various electronic applications are summarized.A careful introduction of material synthesis,transistor engineering focused on device configuration,dielectric engineering,contact engineering,and material integration are given first.Then 2D transistors for certain electronic applications including digital and analog circuits,heterogeneous integration chips,and sensing circuits are discussed.Moreover,several promising applications(artificial intelligence chips and quantum chips)based on specific mechanism devices are introduced.Finally,the challenges for 2D materials encountered in achieving circuit-level or system-level applications are analyzed,and potential development pathways or roadmaps are further speculated and outlooked. 展开更多
关键词 Two-dimensional materials ROADMAP Integrated circuits Post-Moore era
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Analysis of the causes of primary revision after unicompartmental knee arthroplasty: A case series 被引量:3
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作者 Jin-Long Zhao Xiao Jin +5 位作者 He-Tao Huang Wei-Yi Yang Jia-Hui Li Ming-Hui Luo jun liu Jian-Ke Pan 《World Journal of Clinical Cases》 SCIE 2024年第9期1560-1568,共9页
BACKGROUND Unicompartmental knee arthroplasty(UKA)has great advantages in the treatment of unicompartmental knee osteoarthritis,but its revision rate is higher than that of total knee arthroplasty.AIM To summarize and... BACKGROUND Unicompartmental knee arthroplasty(UKA)has great advantages in the treatment of unicompartmental knee osteoarthritis,but its revision rate is higher than that of total knee arthroplasty.AIM To summarize and analyse the causes of revision after UKA.METHODS This is a retrospective case series study in which the reasons for the first revision after UKA are summarized.We analysed the clinical symptoms,medical histories,laboratory test results,imaging examination results and treatment processes of the patients who underwent revision and summarized the reasons for primary revision after UKA.RESULTS A total of 13 patients,including 3 males and 10 females,underwent revision surgery after UKA.The average age of the included patients was 67.62 years.The prosthesis was used for 3 d to 72 months.The main reasons for revision after UKA were improper suturing of the surgical opening(1 patient),osteophytes(2 patients),intra-articular loose bodies(2 patients),tibial prosthesis loosening(2 patients),rheumatoid arthritis(1 patient),gasket dislocation(3 patients),anterior cruciate ligament injury(1 patient),and medial collateral ligament injury with residual bone cement(1 patient).CONCLUSION The causes of primary revision after UKA were gasket dislocation,osteophytes,intra-articular loose bodies and tibial prosthesis loosening.Avoidance of these factors may greatly reduce the rate of revision after UKA,improve patient satisfaction and reduce medical burden. 展开更多
关键词 Unicompartmental knee arthroplasty Total knee arthroplasty CAUSES REVISION Case series
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GmSTF accumulation mediated by DELLA protein GmRGAs contributes to coordinating light and gibberellin signaling to reduce plant height in soybean 被引量:1
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作者 Zhuang Li Qichao Tu +7 位作者 Xiangguang Lyu Qican Cheng Ronghuan Ji Chao Qin jun liu Bin liu Hongyu Li Tao Zhao 《The Crop Journal》 SCIE CSCD 2024年第2期432-442,共11页
Plant height influences plant architecture,lodging resistance,and yield performance.It is modulated by gibberellic acid(GA)metabolism and signaling.DELLA proteins,acting as central repressors of GA signaling,integrate... Plant height influences plant architecture,lodging resistance,and yield performance.It is modulated by gibberellic acid(GA)metabolism and signaling.DELLA proteins,acting as central repressors of GA signaling,integrate various environmental and hormonal signals to regulate plant growth and development in Arabidopsis.We examined the role of two DELLA proteins,GmRGAa and GmRGAb,in soybean plant height control.Knockout of these proteins led to longer internodes and increased plant height,primarily by increasing cell elongation.GmRGAs functioned under different light conditions,including red,blue,and far-red light,to repress plant height.Interaction studies revealed that GmRGAs interacted with the blue light receptor GmCRY1b.Consistent with this,GmCRY1b partially regulated plant height via GmRGAs.Additionally,DELLA proteins were found to stabilize the protein GmSTF1/2,a key positive regulator of photomorphogenesis.This stabilization led to increased transcription of GmGA2ox-7b and subsequent reduction in plant height.This study enhances our understanding of DELLA-mediated plant height control,offering Gmrgaab mutants for soybean structure and yield optimization. 展开更多
关键词 DELLA protein GmRGAs GmSTFs Plant height SOYBEAN
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Structural and functional connectivity of the whole brain and subnetworks in individuals with mild traumatic brain injury:predictors of patient prognosis
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作者 Sihong Huang jungong Han +4 位作者 Hairong Zheng Mengjun Li Chuxin Huang Xiaoyan Kui jun liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1553-1558,共6页
Patients with mild traumatic brain injury have a diverse clinical presentation,and the underlying pathophysiology remains poorly understood.Magnetic resonance imaging is a non-invasive technique that has been widely u... Patients with mild traumatic brain injury have a diverse clinical presentation,and the underlying pathophysiology remains poorly understood.Magnetic resonance imaging is a non-invasive technique that has been widely utilized to investigate neuro biological markers after mild traumatic brain injury.This approach has emerged as a promising tool for investigating the pathogenesis of mild traumatic brain injury.G raph theory is a quantitative method of analyzing complex networks that has been widely used to study changes in brain structure and function.However,most previous mild traumatic brain injury studies using graph theory have focused on specific populations,with limited exploration of simultaneous abnormalities in structural and functional connectivity.Given that mild traumatic brain injury is the most common type of traumatic brain injury encounte red in clinical practice,further investigation of the patient characteristics and evolution of structural and functional connectivity is critical.In the present study,we explored whether abnormal structural and functional connectivity in the acute phase could serve as indicators of longitudinal changes in imaging data and cognitive function in patients with mild traumatic brain injury.In this longitudinal study,we enrolled 46 patients with mild traumatic brain injury who were assessed within 2 wee ks of injury,as well as 36 healthy controls.Resting-state functional magnetic resonance imaging and diffusion-weighted imaging data were acquired for graph theoretical network analysis.In the acute phase,patients with mild traumatic brain injury demonstrated reduced structural connectivity in the dorsal attention network.More than 3 months of followup data revealed signs of recovery in structural and functional connectivity,as well as cognitive function,in 22 out of the 46 patients.Furthermore,better cognitive function was associated with more efficient networks.Finally,our data indicated that small-worldness in the acute stage could serve as a predictor of longitudinal changes in connectivity in patients with mild traumatic brain injury.These findings highlight the importance of integrating structural and functional connectivity in unde rstanding the occurrence and evolution of mild traumatic brain injury.Additionally,exploratory analysis based on subnetworks could serve a predictive function in the prognosis of patients with mild traumatic brain injury. 展开更多
关键词 cognitive function CROSS-SECTION FOLLOW-UP functional connectivity graph theory longitudinal study mild traumatic brain injury prediction small-worldness structural connectivity subnetworks whole brain network
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Magnesium-L-threonate treats Alzheimer's disease by modulating the microbiota-gut-brain axis
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作者 Wang Liao Jiana Wei +10 位作者 Chongxu liu Haoyu Luo Yuting Ruan Yingren Mai Qun Yu Zhiyu Cao Jiaxin Xu Dong Zheng Zonghai Sheng Xianju Zhou jun liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2281-2289,共9页
Disturbances in the microbiota-gut-brain axis may contribute to the development of Alzheimer's disease. Magnesium-L-threonate has recently been found to have protective effects on learning and memory in aged and A... Disturbances in the microbiota-gut-brain axis may contribute to the development of Alzheimer's disease. Magnesium-L-threonate has recently been found to have protective effects on learning and memory in aged and Alzheimer's disease model mice. However, the effects of magnesium-L-threonate on the gut microbiota in Alzheimer's disease remain unknown. Previously, we reported that magnesium-L-threonate treatment improved cognition and reduced oxidative stress and inflammation in a double-transgenic line of Alzheimer's disease model mice expressing the amyloid-β precursor protein and mutant human presenilin 1(APP/PS1). Here, we performed 16S r RNA amplicon sequencing and liquid chromatography-mass spectrometry to analyze changes in the microbiome and serum metabolome following magnesium-Lthreonate exposure in a similar mouse model. Magnesium-L-threonate modulated the abundance of three genera in the gut microbiota, decreasing Allobaculum and increasing Bifidobacterium and Turicibacter. We also found that differential metabolites in the magnesiumL-threonate-regulated serum were enriched in various pathways associated with neurodegenerative diseases. The western blotting detection on intestinal tight junction proteins(zona occludens 1, occludin, and claudin-5) showed that magnesium-L-threonate repaired the intestinal barrier dysfunction of APP/PS1 mice. These findings suggest that magnesium-L-threonate may reduce the clinical manifestations of Alzheimer's disease through the microbiota-gut-brain axis in model mice, providing an experimental basis for the clinical treatment of Alzheimer's disease. 展开更多
关键词 Alzheimer's disease APP/PS1 double-transgenic Alzheimer's disease mouse model inflammation intestinal barrier dysfunction magnesium-L-threonate microbiome microbiota-gut-brain axis oxidative stress serum metabolites
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Geometry and formation mechanism of tension gashes and their implication on the hydrocarbon accumulation in the deep-seated strata of sedimentary basin:A case from Shunnan area of Tarim Basin
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作者 Yan-Nan Du Kong-You Wu +4 位作者 Yin liu Yan-Ying Li Zi-Cheng Cao You-Wei Cui jun liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期87-99,共13页
With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention recently.Affected by multi-stage tectonic ... With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention recently.Affected by multi-stage tectonic movements,the strike-slip faults have controlled the distribution of hydrocarbon resources owing to the special fault characteristics and fault-related structures.In contrast,the kinematics and formation mechanism of strike-slip faults in buried sedimentary basins are difficult to investigate,limiting the discussion of these faults and hydrocarbon accumulation.In this study,we identified the characteristics of massive sigmoidal tension gashes(STGs)that formed in the Shunnan area of the Tarim Basin.High-resolution three-dimensional seismic data and attribute analyses were used to investigate their geometric and kinematic characteristics.Then,the stress state of each point of the STGs was calculated using seismic curvature attributes.Finally,the formation mechanism of the STGs and their roles in controlling hydrocarbon migration and accumulation were discussed.The results suggest that:(1)the STGs developed in the Shunnan area have a wide distribution,with a tensile fault arranged in an enéchelon pattern,showing an S-shaped bending.These STGs formed in multiple stages,and differential rotation occurred along the direction of strike-slip stress during formation.(2)Near the principal displacement zone of the strike-slip faults,the stress value of the STGs was higher,gradually decreasing at both ends.The shallow layer deformation was greater than the deep layer deformation.(3)STGs are critical for connecting source rocks,migrating oil and gas,sealing horizontally,and developing efficient reservoirs.This study not only provides seismic evidence for the formation and evolution of super large STGs,but also provides certain guidance for oil and gas exploration in this area. 展开更多
关键词 Tarim Basin Sigmoidal tension gashes Seismic attributes Shear stress calculation Formation mechanism Reservoir control
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Evolution of pore systems in low-maturity oil shales during thermal upgrading--Quantified by dynamic SEM and machine learning
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作者 jun liu Xue Bai Derek Elsworth 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1739-1750,共12页
In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically evolves.We characterize this response for a heated substrate concurrently imaged by SEM.We systematically follow the... In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically evolves.We characterize this response for a heated substrate concurrently imaged by SEM.We systematically follow the evolution of pore quantity,size(length,width and cross-sectional area),orientation,shape(aspect ratio,roundness and solidity)and their anisotropy—interpreted by machine learning.Results indicate that heating generates new pores in both organic matter and inorganic minerals.However,the newly formed pores are smaller than the original pores and thus reduce average lengths and widths of the bedding-parallel pore system.Conversely,the average pore lengths and widths are increased in the bedding-perpendicular direction.Besides,heating increases the cross-sectional area of pores in low-maturity oil shales,where this growth tendency fluctuates at<300℃ but becomes steady at>300℃.In addition,the orientation and shape of the newly-formed heating-induced pores follow the habit of the original pores and follow the initial probability distributions of pore orientation and shape.Herein,limited anisotropy is detected in pore direction and shape,indicating similar modes of evolution both bedding-parallel and bedding-normal.We propose a straightforward but robust model to describe evolution of pore system in low-maturity oil shales during heating. 展开更多
关键词 Low-maturity oil shale Pore elongation Organic matter pyrolysis In-situthermal upgrading Scanning electron microscopy(SEM) Machine learning
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OsDA1 positively regulates grain width in rice
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作者 Cong Li jun liu +4 位作者 Liya Zhang Tao Li Hongyu Li Bin liu Tao Zhao 《The Crop Journal》 SCIE CSCD 2024年第1期92-101,共10页
The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed i... The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed in young spikelets and glumes.Its overexpression led to enlarged seeds with increased width and decreased length/width ratio(LWR)and knocking out OsDA1 reduced grain width and increased grain length and LWR.A R310K point mutation in the DA1-like domain is a potential target for breeding for increased grain width and length.OsDA1 interacted with TCP gene-family proteins to regulate grain size and shape.Our findings deepen our understanding of the molecular mechanisms underlying grain size regulation and provide useful information for improving grain yield. 展开更多
关键词 RICE Osda1 Grain size Grain shape Grain length/width ratio TCP
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Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials
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作者 Rui Zhao Jian Zheng +4 位作者 Jin Guo Yunbo Shi Hengzhen Feng jun Tang jun liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期217-224,共8页
In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation pr... In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped lattices.The effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and analyzed.The target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent lattices.The proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k Hz.After the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target frequency.These results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment. 展开更多
关键词 Star-shaped metamaterials BROADBAND Vibration attenuation Low-frequency ultrasound vibration Transmission loss
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The role of polyurethane foam compressible layer in the mechanical behaviour of multi-layer yielding supports for deep soft rock tunnels
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作者 Haibo Wang Fuming Wang +3 位作者 Chengchao Guo Lei Qin jun liu Tongming Qu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4554-4569,共16页
The polyurethane foam(PU)compressible layer is a viable solution to the problem of damage to the secondary lining in squeezing tunnels.Nevertheless,the mechanical behaviour of the multi-layer yielding supports has not... The polyurethane foam(PU)compressible layer is a viable solution to the problem of damage to the secondary lining in squeezing tunnels.Nevertheless,the mechanical behaviour of the multi-layer yielding supports has not been thoroughly investigated.To fill this gap,large-scale model tests were conducted in this study.The synergistic load-bearing mechanics were analyzed using the convergenceconfinement method.Two types of multi-layer yielding supports with different thicknesses(2.5 cm,3.75 cm and 5 cm)of PU compressible layers were investigated respectively.Digital image correlation(DIC)analysis and acoustic emission(AE)techniques were used for detecting the deformation fields and damage evolution of the multi-layer yielding supports in real-time.Results indicated that the loaddisplacement relationship of the multi-layer yielding supports could be divided into the crack initiation,crack propagation,strain-hardening,and failure stages.Compared with those of the stiff support,the toughness,deformability and ultimate load of the yielding supports were increased by an average of 225%,61%and 32%,respectively.Additionally,the PU compressible layer is positioned between two primary linings to allow the yielding support to have greater mechanical properties.The analysis of the synergistic bearing effect suggested that the thickness of PU compressible layer and its location significantly affect the mechanical properties of the yielding supports.The use of yielding supports with a compressible layer positioned between the primary and secondary linings is recommended to mitigate the effects of high geo-stress in squeezing tunnels. 展开更多
关键词 Multi-layer yielding supports Polyurethane foam compressible layer Synergistic mechanism Large-scale model test Deep soft rock tunnels
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Microstructure and mechanical properties of Co-28Cr-6Mo-0.22C investment castings by current solution treatment
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作者 Ze-yu Dan jun liu +4 位作者 Jian-lei Zhang Yan-hua Li Yuan-xin Deng Yun-hu Zhang Chang-jiang Song 《China Foundry》 SCIE EI CAS CSCD 2024年第4期369-378,共10页
This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment castings.The findings reveal that the current solution treatment s... This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment castings.The findings reveal that the current solution treatment significantly promotes the dissolution of carbides at a lower temperature.The optimal conditions for solution treatment are determined as a solution temperature of 1,125°C and a holding time of 5.0 min.Under these parameters,the size and volume fraction of precipitated phases in the investment castings are measured as6.2μm and 1.1vol.%.The yield strength,ultimate tensile strength,and total elongation of the Co-28Cr-6Mo-0.22C investment castings are 535 MPa,760 MPa,and 12.6%,respectively.These values exceed those obtained with the conventional solution treatment at 1,200°C for 4.0 h.The findings suggest a phase transformation of M_(23)C_(6)→σ+C following the current solution treatment at 1,125°C for 5.0 min.In comparison,the traditional solution treatment at 1,200°C for 4.0 h leads to the formation of M_(23)C_(6)and M_(6)C carbides.It is noteworthy that the non-thermal effect of the current during the solution treatment modifies the free energy of both the matrix and precipitation phase.This modification lowers the phase transition temperature of the M_(23)C_(6)→σ+C reaction,thereby facilitating the dissolution of carbides.As a result,the current solution treatment approach achieves carbide dissolution at a lower temperature and within a significantly shorter time when compared to the traditional solution treatment methods. 展开更多
关键词 CoCrMo alloy investment castings current solution treatment microstructure mechanical property CARBIDE
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Effect of speed humps on instantaneous traffic emissions in a microscopic model with limited deceleration capacity
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作者 胡宇晨 李启朗 +2 位作者 刘军 王君霞 汪秉宏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期413-420,共8页
As a common transportation facility, speed humps can control the speed of vehicles on special road sections to reduce traffic risks. At the same time, they also cause instantaneous traffic emissions. Based on the clas... As a common transportation facility, speed humps can control the speed of vehicles on special road sections to reduce traffic risks. At the same time, they also cause instantaneous traffic emissions. Based on the classic instantaneous traffic emission model and the limited deceleration capacity microscopic traffic flow model with slow-to-start rules, this paper has investigated the impact of speed humps on traffic flow and the instantaneous emissions of vehicle pollutants in a single lane situation. The numerical simulation results have shown that speed humps have significant effects on traffic flow and traffic emissions. In a free-flow region, the increase of speed humps leads to the continuous rise of CO_(2), NO_(X) and PM emissions. Within some density ranges, one finds that these pollutant emissions can evolve into some higher values under some random seeds. Under other random seeds, they can evolve into some lower values. In a wide moving jam region, the emission values of these pollutants sometimes appear as continuous or intermittent phenomenon. Compared to the refined Na Sch model, the present model has lower instantaneous emissions such as CO_(2), NO_(X) and PM and higher volatile organic components(VOC) emissions. Compared to the limited deceleration capacity model without slow-to-start rules, the present model also has lower instantaneous emissions such as CO_(2), NO_(X) and PM and higher VOC emissions in a wide moving jam region. These results can also be confirmed or explained by the statistical values of vehicle velocity and acceleration. 展开更多
关键词 traffic emissions speed humps slow-to-start rules deceleration capacity
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Investigation into IgG/IgE binding capacity and gut microbiota of digestion products derived from glycated ovalbumin
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作者 Jihua Mao Yanhong Shao +2 位作者 Hui Wang jun liu Zongcai Tu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3633-3641,共9页
Gut microbiota plays an important role in food allergy.The immunoglobulin G(IgG)/immunoglobulin E(IgE)binding capacity and human gut microbiota changes of digestion products derived from glycated ovalbumin(OVA)were in... Gut microbiota plays an important role in food allergy.The immunoglobulin G(IgG)/immunoglobulin E(IgE)binding capacity and human gut microbiota changes of digestion products derived from glycated ovalbumin(OVA)were investigated.Gastrointestinal digestion effectively destroyed the primary structure of glycated OVA,resulting in a significantly higher digestibility than gastric digestion,and more abundant peptides<3 kDa.Moreover,gastric and gastrointestinal digestion products have different fluorescence quenching and red shift of fluorescence peaks,and possess different conformational structures.These changes resulted in a decrease in 28.7%of the IgE binding capacity of gastrointestinal digestion products beyond that of pepsin.Moreover,gastrointestinal digestion products of glycated OVA increased significantly the proportion of Subdoligranulum,Collinsella,and Bifidobacterium.Therefore,gastrointestinal digestion products of glycated OVA altered human intestinal microbiota,reducing the risk of potential allergy. 展开更多
关键词 OVALBUMIN Glycation DIGESTION IgG/IgE binding capacity Gut microbiota
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Low-noise and low-power pixel sensor chip for gas pixel detectors
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作者 Zhuo Zhou Shi-Qiang Zhou +8 位作者 Dong Wang Xiang-Ming Sun Chao-Song Gao Peng-Zhen Zhu Wei-Ping Ren jun liu Mu-Xian Li Chen Lian Chun-Lai Dong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期142-152,共11页
Topmetal-M2 is a large-area pixel sensor chip fabricated using the GSMC 130 nm CMOS process in 2021.The pixel array of Topmetal-M2 consists of pixels of 400 rows×512 columns with a pixel pitch of 45μm×45μm... Topmetal-M2 is a large-area pixel sensor chip fabricated using the GSMC 130 nm CMOS process in 2021.The pixel array of Topmetal-M2 consists of pixels of 400 rows×512 columns with a pixel pitch of 45μm×45μm.The array is divided into 16 subarrays,with pixels of 400 rows×32 columns per subarray.Each pixel incorporates two charge sensors:a diode sensor and a Topmetal sensor.The in-pixel circuit primarily consists of a charge-sensitive amplifier for energy measurements,a discriminator with a peak-holding circuit,and a time-to-amplitude converter for time-of-arrival measurements.The pixel of Topmetal-M2 has a charge input range of~0-3 k e-,a voltage output range of~0-180 mV,and a charge-voltage conversion gain of~59.56μV∕e-.The average equivalent noise charge of Topmetal-M2,which includes the readout electronic system noise,is~43.45 e-.In the scanning mode,the time resolution of Topmetal-M2 is 1 LSB=1.25μs,and the precision is^()7.41μs.At an operating voltage of 1.5 V,Topmetal-M2 has a power consumption of~49 mW∕cm~2.In this article,we provide a comprehensive overview of the chip architecture,pixel working principles,and functional behavior of Topmetal-M2.Furthermore,we present the results of preliminary tests conducted on Topmetal-M2,namely,alpha-particle and soft X-ray tests. 展开更多
关键词 Charge collection Gas detectors Semiconductor detectors X-ray detectors
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NνDEx-100 conceptual design report
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作者 Xi-Guang Cao Yan-Long Chang +35 位作者 Kai Chen Emilio Ciuffoli Li-Min Duan Dong-Liang Fang Chao-Song Gao Surja K.Ghorui Peng-Chong Hu Qiang Hu Si-Yuan Huang Ze-Yu Huang Lei Lang Yu-Lan Li Zhi-Jie Li Tian-Yu Liang jun liu Chen-Gui Lu Fa-Tai Mai Yuan Mei Hao Qiu Xiang-Ming Sun Xiao-Xing Tang Hu-Lin Wang Qian-Ming Wang Le Xiao Mu-Yun Xiao Jian-Yu Xin Nu Xu Peng Yang Yi-Chen Yang Zhen Yang Zong-Yang Yu Dong-Liang Zhang jun-Wei Zhang Cheng-Xin Zhao Dou Zhu NνDEx-100 collaboration 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期18-33,共16页
Observing nuclear neutrinoless double beta (0vββ) decay would be a revolutionary result in particle physics.Observing such a decay would prove that the neutrinos are their own antiparticles,help to study the absolut... Observing nuclear neutrinoless double beta (0vββ) decay would be a revolutionary result in particle physics.Observing such a decay would prove that the neutrinos are their own antiparticles,help to study the absolute mass of neutrinos,explore the origin of their mass,and may explain the matter-antimatter asymmetry in our universe by lepton number violation.We propose developing a time projection chamber (TPC) using high-pressure ^(82)SeF_(6) gas and Topmetal silicon sensors for readout in the China Jinping Underground Laboratory (CJPL) to search for neutrinoless double beta decay of82Se,called the NvDEx experiment.Besides being located at CJPL with the world’s thickest rock shielding,NvDEx combines the advantages of the high Qββ(2.996 MeV) of82Se and the TPC’s ability to distinguish signal and background events using their different topological characteristics.This makes NvDEx unique,with great potential for low-background and high-sensitivity 0 vββsearches.NvDEx-100,a NvDEx experiment phase with 100 kg of SeF_(6)gas,is being built,with plans to complete installation at CJPL by 2025.This report introduces 0 vββ physics,the NvDEx concept and its advantages,and the schematic design of NvDEx-100,its subsystems,and background and sensitivity estimation. 展开更多
关键词 Neutrinoless double beta decay Time projection chamber ^(82)SeF_(6) China Jinping Underground Laboratory
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Enhanced energy density and fast-charging ability via directional particle configuration
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作者 Xiongwei Wu Shanguang lv +6 位作者 Jiabao Li Xingrong Yin Xuewen Wu jun liu Jie Zhang Yuhan Yu Bei Long 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期152-164,I0005,共14页
The limited energy density of lithium-ion capacitors poses a significant obstacle to their widespread application,primarily stemming from the inability of the electrodes to simultaneously fulfill both high energy dens... The limited energy density of lithium-ion capacitors poses a significant obstacle to their widespread application,primarily stemming from the inability of the electrodes to simultaneously fulfill both high energy density and rapid charging requirements.Experimental data demonstrate that a directional particle configuration can enhance charging speed while maintaining high-capacity density,but it is rarely discussed.Here,we have developed a particle-level electrochemical model capable of reconstructing an electrode with a directional particle configuration.By employing this method,an investigation was conducted to explore how the spatial morphology characteristics of particle configuration impact the energy storage characteristics of electrodes.Results demonstrate that rational particle configuration can effectively enhance the transport of lithium ions and create additional space for lithium-ion storage.With the same particle size distribution,the best electrode can increase the discharge capacity by up to132.4% and increase the charging SOC by 11.3% compared to the ordinary electrode under the condition of 6 C.These findings provide a further understanding of the energy storage mechanism inside the anisotropic particle distribution electrode,which is important for developing high-performance lithium-ion capacitors. 展开更多
关键词 SUPERCAPACITOR Gradient design strategies Energy storage Charge transport
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