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数字福祉视角下的银发群体智能手机依赖的动机与情感因素研究
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作者 钟智锦 纪晓玉 黄佰全 《全球传媒学刊》 2023年第6期21-38,共18页
智能手机依赖作为数字实践中功能失调的表现,在银发人群数字融入过程中时常发生。本研究使用结构方程模型对银发群体智能手机依赖的形成机制进行分析,旨在阐释数字化社会中银发群体的数字融入实践及其伴随的数字福祉问题。研究发现,情... 智能手机依赖作为数字实践中功能失调的表现,在银发人群数字融入过程中时常发生。本研究使用结构方程模型对银发群体智能手机依赖的形成机制进行分析,旨在阐释数字化社会中银发群体的数字融入实践及其伴随的数字福祉问题。研究发现,情感因素(孤独感)对银发群体智能手机依赖的直接关联是最稳定的,动机因素对智能手机依赖的直接影响存在内部差异,社会规范、表达需求、信息需求、娱乐需求的直接效果显著,但社交需求不显著,并且上述因素在不同人口特质的银发群体中,作用机制有所差异。研究还讨论了智能手机使用程度的中介效果,发现智能手机使用程度在表达需求和智能手机依赖之间具有稳定的中介效果。 展开更多
关键词 银发群体 智能手机 数字福祉 数字依赖 使用动机
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Functional analysis of a novel C-glycosyltransferase in the orchid Dendrobium catenatum 被引量:5
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作者 Zhiyao Ren xiaoyu ji +8 位作者 Zhenbin jiao Yingyi Luo Guo-Qiang Zhang Shengchang Tao Zhouxi Lei jing Zhang Yuchen Wang Zhong-jian Liu Gang Wei 《Horticulture Research》 SCIE 2020年第1期1426-1443,共18页
Flavonoids,which are a diverse class of phytonutrients,are used by organisms to respond to nearly all abiotic stresses and are beneficial for human health.Glycosyltransferase,used during the last step of flavonoid bio... Flavonoids,which are a diverse class of phytonutrients,are used by organisms to respond to nearly all abiotic stresses and are beneficial for human health.Glycosyltransferase,used during the last step of flavonoid biosynthesis,is important in flavonoid enrichment.However,little is known about glycosyltransferase in the orchid Dendrobium catenatum(D.officinale).In this study,we isolated a novel C-glycosyltransferase(designated DcaCGT)from the orchid D.catenatum by identifying and analyzing 82 putative genes in the GT1 family.DcaCGT could specifically catalyze not only di-C-glycosylation but also O-glycosylation.Apart from the normal function of catalyzing 2-hydroxynaringenin and phloretin to the respective di-C-glycosides,DcaCGT also catalyzes apigenin to cosmosiin.Targeted metabolic profiling of the substrates(2-hydroxynaringenin,phloretin,and apigenin)and products(vitexin,isovitexin,vicenin-2,nothofagin,3’,5’-di-C-glucosylphloretin,and cosmosiin)in different tissues showed that vicenin-2 was the most abundant product of this novel enzyme.Cosmosiin was detected in flowers and flower buds.We also established that DcaCGT functions expanded throughout the evolution of D.catenatum.Residual OGT activity may help D.catenatum resist drought stress.Our study illustrates the function,origin,and differentiation of DcaCGT and provides insights into glycosylation and molecular propagation processes,which can be used to improve the production of flavonoids by the cultivated medicinal plant D.catenatum. 展开更多
关键词 FLOWERS expanded DROUGHT
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SENet优化的Deeplabv3+淡水鱼体语义分割 被引量:1
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作者 王红君 季晓宇 +2 位作者 赵辉 岳有军 李明心(译) 《智能化农业装备学报(中英文)》 2021年第1期36-43,共8页
淡水鱼头、腹、鳍的各部分快速识别与精准定位是机器人实现淡水鱼快速抓取,精确切割、提升作业效率关键技术的前提。针对深度学习的淡水鱼体语义分割算法在编码特征提取阶段产生大量无效的特征通道,以及网络不断下采样和池化操作使得鱼... 淡水鱼头、腹、鳍的各部分快速识别与精准定位是机器人实现淡水鱼快速抓取,精确切割、提升作业效率关键技术的前提。针对深度学习的淡水鱼体语义分割算法在编码特征提取阶段产生大量无效的特征通道,以及网络不断下采样和池化操作使得鱼体某些细节信息被丢失,网络性能下降、边缘分割效果不佳的问题,提出了一种基于SENet优化后的Deeplabv3+淡水鱼头、腹、鳍的语义分割算法。利用空洞/带孔卷积(dilated/atrous convolutions)实现扩展感受野,克服细节信息丢失,达到准确定位的目的,同时SENet的优化使得Deeplabv3+通过学习的方式提升淡水鱼有用的特征并抑制对当前任务用处不大的特征,最终淡水鱼各部分的语义分割平均交并比(MIoU)在自建的淡水鱼数据集上达到了93%左右,性能得到了明显提升并达到了目前先进分割水平。 展开更多
关键词 识别 定位 深度学习 特征通道 感受野 语义分割
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Role of chemokines in the hepatocellular carcinoma microenvironment and their translational value in immunotherapy
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作者 Yijun Wang Mengyu Sun +7 位作者 Tongyue Zhang Yangyang Feng Xiangyuan Luo Meng Xie xiaoyu ji Danfei Liu Wenjie Huang Limin Xia 《Oncology and Translational Medicine》 CAS 2022年第1期1-17,共17页
The difficulty of early diagnosis,high tumor heterogeneity,and high recurrence and metastasis rates lead to an unsatisfactory treatment status for hepatocellular carcinoma(HCC).HCC is a typical inflammation-driven tum... The difficulty of early diagnosis,high tumor heterogeneity,and high recurrence and metastasis rates lead to an unsatisfactory treatment status for hepatocellular carcinoma(HCC).HCC is a typical inflammation-driven tumor.Chronic inflammation allows nascent tumors to escape immunosurveillance.Chemokines are small,soluble,secreted proteins that can regulate the activation and trafficking of immune cells during inflammation.Several studies have shown that various chemokines with overarching functions disrupt the immune microenvironment during the initiation and progression of HCC.The dysregulated chemokine network in HCC contributes to multiple malignant processes,including angiogenesis,tumor proliferation,migration,invasion,tumor low response,and resistance to immune therapy.Here,we summarize the current studies focusing on the role of chemokines and their receptors in the HCC immune microenvironment,highlighting potential translational therapeutic uses for modulating the chemokine system in HCC. 展开更多
关键词 hepatocellular carcinoma CHEMOKINE chemokine receptor tumor microenvironment immune therapy therapeutic target
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Research Progress and Challenges on Persistent Organic Pollutants in Lakes
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作者 Wei Guo xiaoyu ji +2 位作者 Zhengfei Yu Hongchen jiang Xiangyu Guan 《Journal of Earth Science》 SCIE CAS CSCD 2024年第2期729-736,共8页
Lakes are the main reservoirs of persistent organic pollutants(POPs)from land,atmo sphere and rivers.POPs in lakes undergo complex exchange,transformation,and degradation between water-air-sediment-biota interfaces,wh... Lakes are the main reservoirs of persistent organic pollutants(POPs)from land,atmo sphere and rivers.POPs in lakes undergo complex exchange,transformation,and degradation between water-air-sediment-biota interfaces,which are constrained and regulated by various physical,chemical and biological factors.POPs can affect ecological conditions,chemical properties of water and sedi ments,and biodiversity of the lake system.Therefore,it is important to study the sources,migration,transformation,environmental behavior and ecological impacts of POPs in lake ecosystems.This re view summarizes research progress on detection technologies,diversity and origins,historical records,migration and transformation,distribution patterns,degradation and toxic effects of POPs in lakes.Fi nally,future directions related to POPs in lakes were summarized. 展开更多
关键词 persistent organic pollutants(POPs) LAKES TRANSFORMATION DEGRADATION microbes environment geolgogy
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Efficient wide-bandgap perovskite solar cells with open-circuit voltage deficit below 0.4 V via hole-selective interface engineering
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作者 xiaoyu ji Shuo Zhang +5 位作者 Furong Yu Huidong Zhang Liqing Zhan Yue Hu Wei-Hong Zhu Yongzhen Wu 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第6期2102-2110,共9页
Wide-bandgap mixed-halide perovskite solar cells(WBG-PSCs)are promising top cells for efficient tandem photovoltaics to achieve high power conversion efficiency(PCE)at low cost.However,the open-circuit voltage(V_(OC))... Wide-bandgap mixed-halide perovskite solar cells(WBG-PSCs)are promising top cells for efficient tandem photovoltaics to achieve high power conversion efficiency(PCE)at low cost.However,the open-circuit voltage(V_(OC))of WBG-PSCs is still unsatisfactory as the V_(OC)-deficit is generally larger than 0.45 V.Herein,we report a buried interface engineering strategy that substantially improves the V_(OC)of WBG-PSCs by inserting amphiphilic molecular hole-selective materials featuring with a cyanovinyl phosphonic acid(CPA)anchoring group between the perovskite and substrate.The assembly and redistribution of CPA-based amphiphilic molecules at the perovskite-substrate buried interface not only promotes the growth of a low-defect crystalline perovskite thin film,but also suppresses the photo-induced halide phase separation.The energy level alignment between wide-bandgap perovskite and the hole-selective layer is further improved by modulating the substituents on the triphenylamine donor moiety(methoxyls for MPA-CPA,methyls for Me PA-CPA,and bare TPA-CPA).Using a 1.68 e V bandgap perovskite,the Me PA-CPA-based devices achieved an unprecedentedly high V_(OC)of 1.29 V and PCE of 22.3%under standard AM 1.5 sunlight.The V_(OC)-deficit(<0.40 V)is the lowest value reported for WBG-PSCs.This work not only provides an effective approach to decreasing the V_(OC)-deficit of WBG-PSCs,but also confirms the importance of energy level alignment at the charge-selective layers in PSCs. 展开更多
关键词 cyanovinyl phosphonic acid energy level alignment hole-selective material open-circuit voltage wide-bandgap perovskite
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铈基催化剂用于NH_3选择性催化氧化的研究进展
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作者 蔡彦迪 纪小雨 +6 位作者 张弼凤 穆屹波 仝庆 刘安鼐 谭伟 刘福东 董林 《中国科学:化学》 CAS CSCD 北大核心 2024年第3期295-308,共14页
逃逸到大气中的氨对人体健康和生态环境均会造成严重危害.为应对工业(固定源)和机动车(移动源)污染控制中造成的氨逃逸问题,氨选择性催化氧化技术得以有效开发,其中高效的催化剂是该技术的核心.铈基材料由于其优越的氧化还原性能、可调... 逃逸到大气中的氨对人体健康和生态环境均会造成严重危害.为应对工业(固定源)和机动车(移动源)污染控制中造成的氨逃逸问题,氨选择性催化氧化技术得以有效开发,其中高效的催化剂是该技术的核心.铈基材料由于其优越的氧化还原性能、可调的表面状态和与金属容易形成强相互作用被广泛用于氨氧化催化剂的制备.本文对当前铈基氨选择性催化氧化催化剂的研究进展进行了系统总结、归纳和评述,并对该领域的未来发展方向提出了展望. 展开更多
关键词 氨逃逸 氨选择性催化氧化 铈基催化剂
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Sources,dynamics in vivo,and application of astaxanthin and lutein in laying hens:A review 被引量:2
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作者 Hanyi Shi Xuejuan Deng +2 位作者 xiaoyu ji Ning Liu Huiyi Cai 《Animal Nutrition》 SCIE CAS CSCD 2023年第2期324-333,共10页
Astaxanthin(Ax)and lutein are important fat-soluble pigments and essential nutrients for human and animal health.Haematococcus pluvialis microalga and Phaffia rhodozyma yeast are ideal species for commercial Ax produc... Astaxanthin(Ax)and lutein are important fat-soluble pigments and essential nutrients for human and animal health.Haematococcus pluvialis microalga and Phaffia rhodozyma yeast are ideal species for commercial Ax production.Marigold flowers are a main source of commercial lutein.Dynamics of dietary Ax and lutein in the gastrointestinal tract are similar to lipids,but their activities are tremendously challenged by many physiological and dietary factors;few data are available about these in poultry.Dietary Ax and lutein have insignificant effects on egg production and egg physical properties,but have pronounced effects on yolk color,nutrition,and functionality.The two pigments can also enhance antioxidative capacity and immune function of laying hens.A few studies have shown that Ax and lutein can improve fertilization and hatchability of laying hens.Considering the pigmentation and health benefits of Ax and lutein from hen feed to human food,the commercial availability,chicken yolk improvement,and immune function of Ax and lutein are the focuses of this review.The potential roles of carotenoids in the cytokine storm and gut microbiota are also briefly presented.The bioavailability,metabolism,and deposition of Ax and lutein in laying hens are suggested for future research. 展开更多
关键词 Application ASTAXANTHIN Egg yolk Food chain Laying hen LUTEIN
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Advanced inorganic/polymer hybrid electrolytes for all-solid-state lithium batteries 被引量:3
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作者 xiaoyu ji Yiruo ZHANG +5 位作者 Mengxue CAO Quanchao GU Honglei WANG jinshan YU Zi-Hao GUO Xingui ZHOU 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2022年第6期835-861,共27页
Solid-state batteries have become a frontrunner in humankind’s pursuit of safe and stable energy storage systems with high energy and power density.Electrolyte materials,currently,seem to be the Achilles’heel of sol... Solid-state batteries have become a frontrunner in humankind’s pursuit of safe and stable energy storage systems with high energy and power density.Electrolyte materials,currently,seem to be the Achilles’heel of solid-state batteries due to the slow kinetics and poor interfacial wetting.Combining the merits of solid inorganic electrolytes(SIEs)and solid polymer electrolytes(SPEs),inorganic/polymer hybrid electrolytes(IPHEs)integrate improved ionic conductivity,great interfacial compatibility,wide electrochemical stability window,and high mechanical toughness and flexibility in one material,having become a sought-after pathway to high-performance all-solid-state lithium batteries.Herein,we present a comprehensive overview of recent progress in IPHEs,including the awareness of ion migration fundamentals,advanced architectural design for better electrochemical performance,and a perspective on unconquered challenges and potential research directions.This review is expected to provide a guidance for designing IPHEs for next-generation lithium batteries,with special emphasis on developing high-voltage-tolerance polymer electrolytes to enable higher energy density and three-dimensional(3D)continuous ion transport highways to achieve faster charging and discharging. 展开更多
关键词 solid-state electrolytes(SSEs) hybrid electrolytes energy density electrical energy storage(EES) lithium batteries
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Polydopamine-mediated synthesis of Si@carbon@graphene aerogels for enhanced lithium storage with long cycle life 被引量:1
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作者 Ningning Li Yi Liu +7 位作者 xiaoyu ji jiaxin Feng Kai Wang jiayue Xie Guanglu Lei Xianghong Liu Xiangxin Guo Jun Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第12期3787-3792,共6页
The application of Si as the anode materials for lithium-ion batteries(LIBs) is still severely hindered by the rapid capacity decay due to the structural damage caused by large volume change(> 300%) during cycling.... The application of Si as the anode materials for lithium-ion batteries(LIBs) is still severely hindered by the rapid capacity decay due to the structural damage caused by large volume change(> 300%) during cycling. Herein, a three-dimensional(3 D) aerogel anode of Si@carbon@graphene(SCG) is rationally constructed via a polydopamine-assisted strategy. Polydopamine is coated on Si nanoparticles to serve as an interface linker to initiate the assembly of Si and graphene oxide, which plays a crucial role in the successful fabrication of SCG aerogels. After annealing the polydopamine is converted into N-doped carbon(N-carbon) coatings to protect Si materials. The dual protection from N-carbon and graphene aerogels synergistically improves the structural stability and electronic conductivity of Si, thereby leading to the significantly improved lithium storage properties. Electrochemical tests show that the SCG with optimized graphene content delivers a high capacity(712 m Ah/g at 100 m A/g) and robust cycling stability(402 m Ah/g at 1 A/g after 1500 cycles). Furthermore, the full cell using SCG aerogels as anode exhibits a reversible capacity of 187.6 m Ah/g after 80 cycles at 0.1 A/g. This work provides a plausible strategy for developing Si anode in LIBs. 展开更多
关键词 Si anode Carbon coating GRAPHENE AEROGEL Cycle life
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