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肠镜检查在评估免疫检查点抑制剂相关结肠炎中的临床意义
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作者 于涛 王鑫 +3 位作者 曹晓仓 刘夏 王丹 钟殿胜 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第17期909-914,共6页
目的:明确肠镜检查在免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)诱导结肠炎患者诊疗随访中的作用和价值。方法:回顾性选取2020年12月至2023年12月于天津医科大学总医院接受ICIs治疗后出现结肠炎并进行肠镜检查的患者,分析其... 目的:明确肠镜检查在免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)诱导结肠炎患者诊疗随访中的作用和价值。方法:回顾性选取2020年12月至2023年12月于天津医科大学总医院接受ICIs治疗后出现结肠炎并进行肠镜检查的患者,分析其治疗效果以及预后与肠镜病理特征的关系。结果:进行肠镜检查的ICIs相关结肠炎患者临床腹泻程度均为3度以上,镜下可见黏膜红斑、渗出、糜烂、血管纹理消失以及水肿等弥漫性炎症特征,其中溃疡直径大于1 cm和(或)深于2 mm提示肠炎预后不良;病理组织学可见隐窝炎和隐窝脓肿等腺体结构改变;显微镜下肠炎患者肠镜表现与病理不一致,应多点深部取材。结论:ICIs相关结肠炎的毒性分级不应只局限于临床表现,应参考肠镜特征和病理组织学特点进行多维度分层,乙状结肠镜由于其操作便捷和良好耐受性可作为结肠炎患者随访的重要手段。 展开更多
关键词 免疫检查点抑制剂 不良反应 结肠炎 肠镜
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STAT3 ameliorates truncated tau-induced cognitive deficits 被引量:2
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作者 Bingge Zhang Huali Wan +7 位作者 Maimaitijiang Maierwufu Qian Liu Ting Li Ye He xin wang Gongping Liu Xiaoyue Hong Qiong Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期915-922,共8页
Proteolytic cleavage of tau by asparagine endopeptidase(AEP)creates tau-N368 fragments,which may drive the pathophysiology associated with synaptic dysfunction and memory deterioration in the brain of Alzheimer’s dis... Proteolytic cleavage of tau by asparagine endopeptidase(AEP)creates tau-N368 fragments,which may drive the pathophysiology associated with synaptic dysfunction and memory deterioration in the brain of Alzheimer’s disease patients.Nonetheless,the molecular mechanisms of truncated tau-induced cognitive deficits remain unclear.Evidence suggests that signal transduction and activator of transcription-3(STAT3)is associated with modulating synaptic plasticity,cell apoptosis,and cognitive function.Using luciferase reporter assays,electrophoretic mobility shift assays,western blotting,and immunofluorescence,we found that human tau-N368 accumulation inhibited STAT3 activity by suppressing STAT3 translocation into the nucleus.Overexpression of STAT3 improved tau-N368-induced synaptic deficits and reduced neuronal loss,thereby improving the cognitive deficits in tau-N368 mice.Moreover,in tau-N368 mice,activation of STAT3 increased N-methyl-D-aspartic acid receptor levels,decreased Bcl-2 levels,reversed synaptic damage and neuronal loss,and thereby alleviated cognitive deficits caused by tau-N368.Taken together,STAT3 plays a critical role in truncated tau-related neuropathological changes.This indicates a new mechanism behind the effect of tau-N368 on synapses and memory deficits.STAT3 can be used as a new molecular target to treat tau-N368-induced protein pathology. 展开更多
关键词 Alzheimer’s disease apoptosis cognitive deficit memory neurodegenerative disease neuron loss N-methyl-D-aspartic acid receptor STAT3 SYNAPSE tau-N368
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神奇“魔法条”之新冠病毒的快速检测
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作者 杨迪 魏嘉怡 +4 位作者 翟红 王昕 孙太明 宋浩乐 王海雁 《大学化学》 CAS 2024年第4期373-381,共9页
胶体金作为商业化的即时检验POCT(point-of-care test)免疫层析技术中最广泛的标记物之一,具有显著的颜色特征,后期无需可视化改造,且形态稳定、环境友好。本文试纸条制作过程简单,不需要大型贵重仪器。采用柠檬酸三钠还原氯金酸制备胶... 胶体金作为商业化的即时检验POCT(point-of-care test)免疫层析技术中最广泛的标记物之一,具有显著的颜色特征,后期无需可视化改造,且形态稳定、环境友好。本文试纸条制作过程简单,不需要大型贵重仪器。采用柠檬酸三钠还原氯金酸制备胶体金,将胶体金标记在新冠病毒的核衣壳N蛋白抗体上,通过在免疫层析试纸条可视区形成类似三明治结构的抗体-抗原-抗体夹心复合物,并以此复合物的红色检测线作为新冠病毒的定性分析依据。该检测方法裸眼可测、操作简单、且快速(10 min)、灵敏(检测限为0.5 ng∙mL^(−1))、低成本(每条不超过5元)。实验过程可以引导学生体验生命体系中抗原抗体相互作用引发的特异性生命化学反应,激发学生对化学、生物、生命科学和纳米材料等学科相互融合的可视化快检技术的浓厚研究兴趣。 展开更多
关键词 胶体金 POCT 免疫层析 新冠病毒
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Effect of Interface Form on Creep Failure and Life of Dissimilar Metal Welds Involving Nickel-Based Weld Metal and Ferritic Base Metal 被引量:1
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作者 Xiaogang Li Junfeng Nie +2 位作者 xin wang Kejian Li Haiquan Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期265-285,共21页
For dissimilar metal welds(DMWs)involving nickel-based weld metal(WM)and ferritic heat resistant steel base metal(BM)in power plants,there must be an interface between WM and BM,and this interface suffers mechanical a... For dissimilar metal welds(DMWs)involving nickel-based weld metal(WM)and ferritic heat resistant steel base metal(BM)in power plants,there must be an interface between WM and BM,and this interface suffers mechanical and microstructure mismatches and is often the rupture location of premature failure.In this study,a new form of WM/BM interface form,namely double Y-type interface was designed for the DMWs.Creep behaviors and life of DMWs containing double Y-type interface and conventional I-type interface were compared by finite element analysis and creep tests,and creep failure mechanisms were investigated by stress-strain analysis and microstructure characterization.By applying double Y-type interface instead of conventional I-type interface,failure location of DMW could be shifted from the WM/ferritic heat-affected zone(HAZ)interface into the ferritic HAZ or even the ferritic BM,and the failure mode change improved the creep life of DMW.The interface premature failure of I-type interface DMW was related to the coupling effect of microstructure degradation,stress and strain concentrations,and oxide notch on the WM/HAZ interface.The creep failure of double Y-type interface DMW was the result of Type IV fracture due to the creep voids and micro-cracks on fine-grain boundaries in HAZ,which was a result of the matrix softening of HAZ and lack of precipitate pinning at fine-grain boundaries.The double Y-type interface form separated the stress and strain concentrations in DMW from the WM/HAZ interface,preventing the trigger effect of oxide notch on interface failure and inhibiting the interfacial microstructure cracking.It is a novel scheme to prolong creep life and enhance reliability of DMW,by means of optimizing the interface form,decoupling the damage factors from WM/HAZ interface,and then changing the failure mechanism and shifting the failure location. 展开更多
关键词 Dissimilar metal weld Nickel-based weld metal Ferritic heat resistant steel INTERFACE Creep strain MICROSTRUCTURE Failure mechanism Creep life
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Adolescent suicide risk factors and the integration of socialemotional skills in school-based prevention programs 被引量:2
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作者 xin-Qiao Liu xin wang 《World Journal of Psychiatry》 SCIE 2024年第4期494-506,共13页
Adolescents are considered one of the most vulnerable groups affected by suicide.Rapid changes in adolescents’physical and mental states,as well as in their lives,significantly and undeniably increase the risk of sui... Adolescents are considered one of the most vulnerable groups affected by suicide.Rapid changes in adolescents’physical and mental states,as well as in their lives,significantly and undeniably increase the risk of suicide.Psychological,social,family,individual,and environmental factors are important risk factors for suicidal behavior among teenagers and may contribute to suicide risk through various direct,indirect,or combined pathways.Social-emotional learning is considered a powerful intervention measure for addressing the crisis of adolescent suicide.When deliberately cultivated,fostered,and enhanced,selfawareness,self-management,social awareness,interpersonal skills,and responsible decision-making,as the five core competencies of social-emotional learning,can be used to effectively target various risk factors for adolescent suicide and provide necessary mental and interpersonal support.Among numerous suicide intervention methods,school-based interventions based on social-emotional competence have shown great potential in preventing and addressing suicide risk factors in adolescents.The characteristics of school-based interventions based on social-emotional competence,including their appropriateness,necessity,cost-effectiveness,comprehensiveness,and effectiveness,make these interventions an important means of addressing the crisis of adolescent suicide.To further determine the potential of school-based interventions based on social-emotional competence and better address the issue of adolescent suicide,additional financial support should be provided,the combination of socialemotional learning and other suicide prevention programs within schools should be fully leveraged,and cooperation between schools and families,society,and other environments should be maximized.These efforts should be considered future research directions. 展开更多
关键词 Adolescent suicide Risk factors Social-emotional skills Social and emotional learning SCHOOL Prevention
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Strong metal–support interaction boosts the electrocatalytic hydrogen evolution capability of Ru nanoparticles supported on titanium nitride 被引量:1
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作者 xin wang Xiaoli Yang +7 位作者 Guangxian Pei Jifa Yang Junzhe Liu Fengwang Zhao Fayi Jin Wei Jiang Haoxi Ben Lixue Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期245-254,共10页
Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-gr... Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-group metal.Herein,based on the idea of strong metal–support interaction(SMSI)regulation,Ru/TiN catalysts with different degrees of TiN overlayer over Ru nanoparticles were fabricated,which were applied to the alkaline electrolytic water.Characterizations reveal that the TiN overlayer would gradually encapsulate the Ru nanoparticles and induce more electron transfer from Ru nanoparticles to TiN support by the Ru–N–Ti bond as the SMSI degree increased.Further study shows that the exposed Ru–TiN interfaces greatly promote the H_(2) desorption capacity.Thus,the Ru/TiN-300 with a moderate SMSI degree exhibits excellent HER performance,with an overpotential of 38 mV at 10 mA cm^(−2).Also,due to the encapsulation role of TiN overlayer on Ru nanoparticles,it displays super long-term stability with a very slight potential change after 24 h.This study provides a deep insight into the influence of the SMSI effect between Ru and TiN on HER and offers a novel approach for preparing efficient and stable HER electrocatalysts through SMSI engineering. 展开更多
关键词 electronic structure hydrogen evolution reaction RUTHENIUM strong metal-support interaction titanium nitride
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Deep learning for joint channel estimation and feedback in massive MIMO systems 被引量:1
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作者 Jiajia Guo Tong Chen +3 位作者 Shi Jin Geoffrey Ye Li xin wang Xiaolin Hou 《Digital Communications and Networks》 SCIE CSCD 2024年第1期83-93,共11页
The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base stations.However,th... The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base stations.However,the accurate CsI is difficult to obtain due to the large amount of feedback overhead caused by massive antennas.In this paper,we propose a deep learning based joint channel estimation and feedback framework,which comprehensively realizes the estimation,compression,and reconstruction of downlink channels in FDD massive MIMO systems.Two networks are constructed to perform estimation and feedback explicitly and implicitly.The explicit network adopts a multi-Signal-to-Noise-Ratios(SNRs)technique to obtain a single trained channel estimation subnet that works well with different SNRs and employs a deep residual network to reconstruct the channels,while the implicit network directly compresses pilots and sends them back to reduce network parameters.Quantization module is also designed to generate data-bearing bitstreams.Simulation results show that the two proposed networks exhibit excellent performance of reconstruction and are robust to different environments and quantization errors. 展开更多
关键词 Channel estimation CSI feedback Deep learning Massive MIMO FDD
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Design Principles and Mechanistic Understandings of Non-Noble-Metal Bifunctional Electrocatalysts for Zinc-Air Batteries 被引量:1
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作者 Yunnan Gao Ling Liu +10 位作者 Yi Jiang Dexin Yu Xiaomei Zheng Jiayi wang Jingwei Liu Dan Luo Yongguang Zhang Zhenjia Shi xin wang Ya‑Ping Deng Zhongwei Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期13-48,共36页
Zinc-air batteries(ZABs)are promising energy storage systems because of high theoretical energy density,safety,low cost,and abundance of zinc.However,the slow multi-step reaction of oxygen and heavy reliance on noble-... Zinc-air batteries(ZABs)are promising energy storage systems because of high theoretical energy density,safety,low cost,and abundance of zinc.However,the slow multi-step reaction of oxygen and heavy reliance on noble-metal catalysts hinder the practical applications of ZABs.Therefore,feasible and advanced non-noble-metal elec-trocatalysts for air cathodes need to be identified to promote the oxygen catalytic reaction.In this review,we initially introduced the advancement of ZABs in the past two decades and provided an overview of key developments in this field.Then,we discussed the work-ing mechanism and the design of bifunctional electrocatalysts from the perspective of morphology design,crystal structure tuning,interface strategy,and atomic engineering.We also included theoretical studies,machine learning,and advanced characterization technologies to provide a comprehensive understanding of the structure-performance relationship of electrocatalysts and the reaction pathways of the oxygen redox reactions.Finally,we discussed the challenges and prospects related to designing advanced non-noble-metal bifunctional electrocatalysts for ZABs. 展开更多
关键词 Zinc-air batteries Bifunctional electrocatalysts Design principles Mechanistic understandings
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Research progress on the water vapor channel within the Yarlung Zsangbo Grand Canyon, China 被引量:1
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作者 Xuelong Chen Yajing Liu +9 位作者 Yaoming Ma Xiangde Xu xin Xu Luhan Li Dianbin Cao Qiang Zhang Gaili wang Maoshan Li Siqiong Luo xin wang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期10-15,共6页
The Second Tibetan Plateau Scientific Expedition and Research Program tasked a research team with the“Investigation of the water vapor channel of the Yarlung Zsangbo Grand Canyon(INVC)”in the southeastern Tibetan Pl... The Second Tibetan Plateau Scientific Expedition and Research Program tasked a research team with the“Investigation of the water vapor channel of the Yarlung Zsangbo Grand Canyon(INVC)”in the southeastern Tibetan Plateau(TP).This paper summarizes the scientific achievements obtained from the data collected by the INVC observation network and highlights the progress in investigating the development of heavy rainfall events associated with water vapor changes.The rain gauge network of the INVC can represent the impacts of the Yarlung Zsangbo Grand Canyon(YGC)topography on precipitation at the hourly scale.The microphysical characteristics of the precipitation in the YGC are different than those in the lowland area.The GPM-IMERG(Integrated MultisatellitE Retrievals for Global Precipitation Measurement)satellite precipitation data for the YGC region should be calibrated before they are used.The meridional water vapor flux through the YGC is more important than the zonal flux for the precipitation over the southeastern TP.The decreased precipitation around the YGC region is partly due to the decreased meridional water vapor flux passing through the YGC.High-resolution numerical models can benefit precipitation forecasting in this region by using a combination of specific schemes that capture the valley wind and water vapor flux along the valley floor. 展开更多
关键词 Water vapor channel Land-air interaction Mountian meteorology Extreme rainfall Observation network
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Application value research of swallowing treatment device combined with swallowing rehabilitation training in the treatment of swallowing disorders after stroke 被引量:1
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作者 Huan Xu Mei Chen +4 位作者 Yu-Li Wu Ya-Fen Lu xin wang Wei Jiang Yuan-Ying Zhang 《World Journal of Clinical Cases》 SCIE 2024年第21期4618-4625,共8页
BACKGROUND Stroke is a common disabling disease,whether it is ischemic stroke or hemorrhagic stroke,both can result in neuronal damage,leading to various manifestations of neurological dysfunction.AIM To explore of th... BACKGROUND Stroke is a common disabling disease,whether it is ischemic stroke or hemorrhagic stroke,both can result in neuronal damage,leading to various manifestations of neurological dysfunction.AIM To explore of the application value of swallowing treatment device combined with swallowing rehabilitation training in the treatment of swallowing disorders after stroke.METHODS This study selected 86 patients with swallowing disorders after stroke admitted to our rehabilitation department from February 2022 to December 2023 as research subjects.They were divided into a control group(n=43)and an observation group(n=43)according to the treatment.The control group received swallowing rehabilitation training,while the observation group received swallowing treatment device in addition to the training.Both groups underwent continuous intervention for two courses of treatment.RESULTS The total effective rate in the observation group(93.02%)was higher than that in the control group(76.74%)(P=0.035).After intervention,the oral transit time,swallowing response time,pharyngeal transit time,and laryngeal closure time decreased in both groups compared to before intervention.In the observation group,the oral transit time,swallowing response time,and pharyngeal transit time were shorter than those in the control group after intervention.However,the laryngeal closure time after intervention in the observation group was compared with that in the control group(P=0.142).After intervention,average amplitude value and duration of the genioglossus muscle group during empty swallowing and swallowing 5 mL of water are reduced compared to before intervention in both groups.After intervention,the scores of the chin-tuck swallowing exercise and the Standardized Swallowing Assessment are both reduced compared to pre-intervention levels in both groups.However,the observation group scores lower than the control group after intervention.Additionally,the Functional Oral Intake Scale scores of both groups are increased after intervention compared to pre-intervention levels,with the observation group scoring higher than the control group after intervention(P<0.001).The cumulative incidence of complications in the observation group is 9.30%,which is lower than the 27.91%in the control group(P=0.027).CONCLUSION The combination of swallowing therapy equipment with swallowing rehabilitation training can improve the muscle movement level of the genioglossus muscle group,enhance swallowing function,and prevent the occurrence of swallowing-related complications after stroke. 展开更多
关键词 Swallowing therapy device Swallowing rehabilitation training STROKE Swallowing disorder Swallowing function
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Development status and prospect of underground thermal energy storage technology 被引量:1
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作者 Ying-nan Zhang Yan-guang Liu +3 位作者 Kai Bian Guo-qiang Zhou xin wang Mei-hua Wei 《Journal of Groundwater Science and Engineering》 2024年第1期92-108,共17页
Underground Thermal Energy Storage(UTES)store unstable and non-continuous energy underground,releasing stable heat energy on demand.This effectively improve energy utilization and optimize energy allocation.As UTES te... Underground Thermal Energy Storage(UTES)store unstable and non-continuous energy underground,releasing stable heat energy on demand.This effectively improve energy utilization and optimize energy allocation.As UTES technology advances,accommodating greater depth,higher temperature and multi-energy complementarity,new research challenges emerge.This paper comprehensively provides a systematic summary of the current research status of UTES.It categorized different types of UTES systems,analyzes the applicability of key technologies of UTES,and evaluate their economic and environmental benefits.Moreover,this paper identifies existing issues with UTES,such as injection blockage,wellbore scaling and corrosion,seepage and heat transfer in cracks,etc.It suggests deepening the research on blockage formation mechanism and plugging prevention technology,improving the study of anticorrosive materials and water treatment technology,and enhancing the investigation of reservoir fracture network characterization technology and seepage heat transfer.These recommendations serve as valuable references for promoting the high-quality development of UTES. 展开更多
关键词 Aquifer thermal energy storage Borehole thermal energy storage Cavern thermal energy storage Thermal energy storage technology Benefit evaluation
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为我国航天事业做出了开创性的重要贡献——中国科学院紫金山天文台应用天体力学和空间目标与碎片研究部巡礼
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作者 王歆 喻圣贤 《大学科普》 2024年第1期51-53,共3页
自1957年10月4日苏联发射人类首颗人造地球卫星斯普特尼克1号,揭开了人类太空探索序幕以来,随着科技的不断发展和进步,人造卫星的应用范围也越来越广泛。如今人造卫星、宇宙飞船等各类空间目标已成为人类探索的重要工具和支撑,推动着人... 自1957年10月4日苏联发射人类首颗人造地球卫星斯普特尼克1号,揭开了人类太空探索序幕以来,随着科技的不断发展和进步,人造卫星的应用范围也越来越广泛。如今人造卫星、宇宙飞船等各类空间目标已成为人类探索的重要工具和支撑,推动着人类社会的不断进步和发展;与此同时,人类太空活动产生的各种废弃物体,对太空活动的影响也引起了国际社会的广泛关注与重视。对太空中人造空间目标与碎片进行探测、跟踪、识别和编目是一切太空活动的基本保障,而空间目标与碎片在运行过程中要受到地球引力、大气阻尼、地球潮汐、日月引力、太阳辐射压等诸多力学因素的综合影响,运动规律异常复杂。 展开更多
关键词 中国科学院 紫金山天文台 地球引力 太空探索 力学因素 天体力学 地球潮汐 空间目标
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Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development
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作者 Baoqi Hu Rui wang +8 位作者 Hanyue Zhang Xiou wang Sijia Zhou Bo Ma Yan Luan xin wang xinlin Chen Zhichao Zhang Qianyan Kang 《Neural Regeneration Research》 SCIE CAS 2025年第3期900-912,共13页
The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and contin... The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation. 展开更多
关键词 bipolar cells differentiation in vivo microglia Müller glia organotypic retinal explant culture postnatal retina development proliferation retinal progenitor cells
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Failure Analysis of Dissimilar Metal Welds between Ferritic Heat Resistant Steels and Austenitic Stainless Steels in Power Plant
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作者 Xiaogang Li Junfeng Nie +2 位作者 xin wang Kejian Li Haiquan Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期306-326,共21页
This study analysed the failure of dissimilar metal welds(DMWs)between ferritic heat resistant steels and austenitic stainless steels and investigated its influencing factors by means of numerical simulation,microstru... This study analysed the failure of dissimilar metal welds(DMWs)between ferritic heat resistant steels and austenitic stainless steels and investigated its influencing factors by means of numerical simulation,microstructure characterization and mechanical property test.Under the long-term high-temperature service condition in practical power plant,the DMW failure mode was along the interface between nickel-based weld metal(WM)and ferritic heat resistant steel,and the failure mechanism was stress/strain concentration,microstructure degradation and oxidation coupling acting on the interface.The numerical simulation results show that interface stress/strain concentration was due to the differences in coefficient of thermal expansion and creep strength,and the degree of stress/strain concentration was related to service time.The ferrite band formed at the WM/ferritic steel interface was prone to cracking,attracting the fracture along the interface.The interface crack allowed oxidation to develop along the WM/ferritic steel interface.During long-term service,the interface stress/strain concentration,microstructure and oxidation all evolved,which synergistically promoted interface failure of DMW.However,only under the long-term service of low stress conditions could trigger the interface failure of DMW.Meanwhile,long-term service would reduce the mechanical strength and plasticity of DMW. 展开更多
关键词 Dissimilar metal weld FAILURE INTERFACE Stress/strain concentration MICROSTRUCTURE OXIDATION
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Regulation of different light conditions for efficient biomass production and protein accumulation of Spirulina platensis
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作者 Yufei ZHANG Xianjun LI +9 位作者 Yuhui LI Shiqi LIU Yanrui CHEN Miao JIA xin wang Lu ZHANG Qiping GAO Liang ZHANG Daoyong YU Baosheng GE 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期174-186,共13页
Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.I... Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.In this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically characterized.Under different colored lights,S.platensis all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light intensities.At the same light intensity,different colored lights show different growth rate of S.platensis following the sequence of red>white>green>yellow>blue.The maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red LED.The energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>yellow.Transcriptomic analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism pathways.This study provides a conducive and efficient way to promote biomass production and protein accumulation of S.platensis by regulating light conditions. 展开更多
关键词 MICROALGAE light emitting diode protein accumulation biomass production transcriptomic analysis
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Mapping soil organic matter in cultivated land based on multi-year composite images on monthly time scales
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作者 Jie Song Dongsheng Yu +4 位作者 Siwei wang Yanhe Zhao xin wang Lixia Ma Jiangang Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1393-1408,共16页
Rapid and accurate acquisition of soil organic matter(SOM)information in cultivated land is important for sustainable agricultural development and carbon balance management.This study proposed a novel approach to pred... Rapid and accurate acquisition of soil organic matter(SOM)information in cultivated land is important for sustainable agricultural development and carbon balance management.This study proposed a novel approach to predict SOM with high accuracy using multiyear synthetic remote sensing variables on a monthly scale.We obtained 12 monthly synthetic Sentinel-2 images covering the study area from 2016 to 2021 through the Google Earth Engine(GEE)platform,and reflectance bands and vegetation indices were extracted from these composite images.Then the random forest(RF),support vector machine(SVM)and gradient boosting regression tree(GBRT)models were tested to investigate the difference in SOM prediction accuracy under different combinations of monthly synthetic variables.Results showed that firstly,all monthly synthetic spectral bands of Sentinel-2 showed a significant correlation with SOM(P<0.05)for the months of January,March,April,October,and November.Secondly,in terms of single-monthly composite variables,the prediction accuracy was relatively poor,with the highest R^(2)value of 0.36 being observed in January.When monthly synthetic environmental variables were grouped in accordance with the four quarters of the year,the first quarter and the fourth quarter showed good performance,and any combination of three quarters was similar in estimation accuracy.The overall best performance was observed when all monthly synthetic variables were incorporated into the models.Thirdly,among the three models compared,the RF model was consistently more accurate than the SVM and GBRT models,achieving an R^(2)value of 0.56.Except for band 12 in December,the importance of the remaining bands did not exhibit significant differences.This research offers a new attempt to map SOM with high accuracy and fine spatial resolution based on monthly synthetic Sentinel-2 images. 展开更多
关键词 soil organic matter Sentinel-2 monthly synthetic images machine learning model spatial prediction
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Timing effect of high temperature exposure on the plasticity of internode and plant architecture in maize
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作者 Binbin Li Xianmin Chen +6 位作者 Tao Deng Xue Zhao Fang Li Bingchao Zhang xin wang Si Shen Shunli Zhou 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期551-565,共15页
The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely de... The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely determined by the temperature conditions it is exposed to over time.Maize is the main cereal crop,and its stem growth and plant architecture are closely related to lodging resistance,and especially sensitive to temperature.However,systematic research on the timing effect of HT on the sequentially developing internode and stem is currently lacking.To identify the timing effect of HT on the morphology and plasticity of the stem in maize,two hybrids(Zhengdan 958(ZD958),Xianyu 335(XY335))characterized by distinct morphological traits in the stem were exposed to a 7-day HT treatment from the V6 to V17 stages(Vn presents the vegetative stage with n leaves fully expanded)in 2019-2020.The results demonstrated that exposure to HT during V6-V12 accelerated the rapid elongation of stems.For instance,HT occurring at V7 and V12 specifically promoted the lengths and weights of the 3rd-5th and 9th-11th internodes,respectively.Meanwhile,HT slowed the growth of internodes adjacent to the promoted internodes.Interestingly,compared with control,the plant height was significantly increased soon after HT treatment,but the promotion effect became narrower at the subsequent flowering stage,demonstrating a self-adjusting mechanism in the maize plant in response to HT.Importantly,HT altered the plant architectures,including a rising of the ear position and increase in the ear position coefficient.XY335 exhibited greater sensitivity in stem development than ZD958 under HT treatment.These findings improve our systematic understanding of the plasticity of internode and plant architecture in response to the timing of HT exposure. 展开更多
关键词 MAIZE high temperature internode growth PLASTICITY plant architecture
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Comparison of nonlinear modeling methods for the composite rubber clamp
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作者 Yiming CAO Hui MA +4 位作者 Xumin GUO Bingfeng ZHAO Hui LI xin wang Bing wang 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期763-778,共16页
The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared innovatively.The unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with experiments.B... The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared innovatively.The unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with experiments.By fitting the identified nonlinear coefficients under different excitation amplitudes,the nonlinear vibration responses of the system are predicted.The results show that the accuracy of the BWM is higher than that of the CSFM,especially in the non-resonant region.However,the optimization time of the BWM is longer than that of the CSFM. 展开更多
关键词 pipeline system nonlinear clamp model composite rubber clamp amplitude-dependent characteristic vibration response experiment
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围产期护理缺失量表的汉化及信效度检验
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作者 丁胜兰 王鑫 +10 位作者 王清霞 沈涓 谢惠莉 付秀娟 廖露茜 陈娇娇 朱莲 黄静 杨思源 黄秀华 张轶岚 《International Journal of Nursing Sciences》 CSCD 2024年第1期106-112,共7页
目的翻译围产期护理缺失量表,并对其进行信度和效度检验,为国内开展围产期护理缺失的量性研究提供可靠的测评工具。方法采用美国矫形外科医师学会循证医学委员会推荐的跨文化调试量表指南对英文版围产期护理缺失量表进行翻译、回译-文... 目的翻译围产期护理缺失量表,并对其进行信度和效度检验,为国内开展围产期护理缺失的量性研究提供可靠的测评工具。方法采用美国矫形外科医师学会循证医学委员会推荐的跨文化调试量表指南对英文版围产期护理缺失量表进行翻译、回译-文化调适及内容验证,形成中文版围产期护理缺失量表,并通过横断面研究验证其信效度。于2023年2月至4月采用便利抽样法,选取西南地区14所不同级别医院491名助产士进行问卷调查。采用项目分析检验中文版量表条目的鉴别度,采用探索性和验证性因子分析评价量表的结构效度,采用内容效度指数和Cronbach'sa系数评价内容效度和信度。结果围产期护理缺失.量表包括A、B两部分。中文版围产期护理缺失量表A部分的项目-总量表相关系数为0.641 -0.866, B部分为0.644~0.819(P<0.01)。A部分和B部分的量表水平内容效度指数均为0.95,条目水平内容效度指数为0.86~1.00。探索性因子分析分别提取了A部分(必要性护理、基本护理和产后护理)和B部分(沟通、人力资源和物质资源)各3个因子,占总方差的70.186%和71.984%。量表A、B部分的Cronbach's a系数分别为0.968、0.940。结论中文版围产期护理缺失量表具有良好的信度和效度,可作为国内评价围产期护理缺失情况和相关原因的工具。未来需要进行更大样本量的研究,以验证该工具在中国本土的适用性。 展开更多
关键词 助产士 护理缺失 围产期护理 信度 调查及问卷 效度
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Effectiveness and safety of combined nimotuzumab and S-1 chemotherapy with concurrent radiotherapy for locally advanced esophageal cancer in malnourished and elderly patients:A prospective phaseⅡstudy
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作者 Guojie Feng Jiao Li +14 位作者 Nuo Yu Ziyu Zheng Xiongtao Yang Lei Deng Tao Zhang Wenqing wang Wenyang Liu Jianyang wang Qinfu Feng Jima Lyu Zefen Xiao Zongmei Zhou Nan Bi Jianjun Qin xin wang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第3期270-281,共12页
Objective:Definitive chemoradiotherapy(dCRT)is the standard treatment for unresectable locally advanced esophageal cancer.However,this treatment is associated with substantial toxicity,and most malnourished or elderly... Objective:Definitive chemoradiotherapy(dCRT)is the standard treatment for unresectable locally advanced esophageal cancer.However,this treatment is associated with substantial toxicity,and most malnourished or elderly patients are unable to complete this therapy.Therefore,there is a need for a more suitable radiotherapy combination regimen for this population.This study was aimed to evaluate the efficacy and safety of a combination regimen comprising chemotherapy with nimotuzumab and S-1 and concurrent radiotherapy for patients with fragile locally advanced esophageal cancer with a high Nutritional Risk Screening 2002(NRS-2002)score.Methods:Eligible patients with unresectable esophageal carcinoma who had an NRS-2002 score of 2 or higher were enrolled.They were treated with S-1 and nimotuzumab with concurrent radiotherapy,followed by surgery or definitive radiotherapy.The primary endpoint was the locoregional control(LRC)rate.Results:A total of 55 patients who met the study criteria were enrolled.After completion of treatment,surgery was performed in 15 patients and radiotherapy was continued in 40 patients.The median follow-up period was 33.3[95%confidence interval(95%CI,31.4−35.1)]months.The LRC rate was 77.2%(95%CI,66.6%−89.4%)at 1 year in the entire population.The overall survival(OS)rate and event-free survival(EFS)rate were 57.5%and 51.5%at 3 years,respectively.Surgery was associated with better LRC[hazard ratio(HR)=0.16;95%CI,0.04−0.70;P=0.015],OS(HR=0.19;95%CI,0.04−0.80;P=0.024),and EFS(HR=0.25;95%CI,0.08−0.75;P=0.013).Most adverse events were of grade 1 or 2,and no severe adverse events occurred.Conclusions:For malnourished or elderly patients with locally advanced esophageal cancer,radiotherapy combined with nimotuzumab and S-1 is effective and has a good safety profile. 展开更多
关键词 Esophageal carcinoma squamous cell carcinoma nutritional risk score NIMOTUZUMAB S-1 definitive chemoradiotherapy
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