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Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2
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作者 Qing He Zhen Wang +5 位作者 Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen 《Neural Regeneration Research》 SCIE CAS 2025年第6期1801-1815,共15页
Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders.... Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain. 展开更多
关键词 AQUAPORIN-4 Ascl1 ASTROCYTE cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 REPROGRAMMING
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Photocatalytic,electrocatalytic and photoelectrocatalytic conversion of methane to alcohol
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作者 Yu Huang Lei Zou +1 位作者 Yuan-Biao Huang Rong Cao 《Chinese Journal of Catalysis》 2025年第3期207-229,共23页
The conversion of the greenhouse gas methane to value-added chemicals such as alcohols is a promising technology to mitigate environmental issue and the energy crisis.Especially,the sustainable photocatalytic,electroc... The conversion of the greenhouse gas methane to value-added chemicals such as alcohols is a promising technology to mitigate environmental issue and the energy crisis.Especially,the sustainable photocatalytic,electrocatalytic and photoelectrocatalytic conversion of methane at ambient conditions is regarded as an alternative technology to replace with thermocatalysis.In this review,we summarize recent advances in photocatalytic,electrocatalytic and photoelectrocatalytic conversion of methane into alcohols.We firstly introduce the general principles of photocatalysis,electrocatalysis and photoelectrocatalysis.Then,we discuss the mechanism for selective activation of C-H bond and following oxygenation over metal,inorganic semiconductor,organic semiconductor,and heterojunction composite systems in the photocatalytic,electrocatalytic and photoelectrocatalytic methane oxidation in detail.Later,we present insights into the construction of effective photocatalyst,electrocatalyst and photoelectrocatalyst for methane conversion into alcohols from the perspective of band structures and active sites.Finally,the challenges and outlook for future designs of photocatalytic,electrocatalytic and photoelectrocatalytic methane oxidation systems are also proposed. 展开更多
关键词 Photocatalysis ELECTROCATALYSIS PHOTOELECTROCATALYSIS Methane conversion ALCOHOL
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Plasma-assisted fabrication of multiscale materials for electrochemical energy conversion and storage
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作者 Chen Li Tengfei Zhang +8 位作者 Zhong Qiu Beirong Ye Xinqi Liang Xin Liu Minghua Chen Xinhui Xia Chen Wang Wangjun Wan Yongqi Zhang 《Carbon Energy》 2025年第2期144-171,共28页
Plasma,the fourth state of matter,is characterized by the presence of charged particles,including ions and electrons.It has been shown to induce unique physical and chemical reactions.Recently,there have been increase... Plasma,the fourth state of matter,is characterized by the presence of charged particles,including ions and electrons.It has been shown to induce unique physical and chemical reactions.Recently,there have been increased applications of plasma technology in the field of multiscale functional materials'preparation,with a number of interesting results.This review will begin by introducing the basic knowledge of plasma,including the definition,typical parameters,and classification of plasma setups.Following this,we will provide a comprehensive review and summary of the applications(phase conversion,doping,deposition,etching,exfoliation,and surface treatment)of plasma in common energy conversion and storage systems,such as electrocatalytic conversion of small molecules,batteries,fuel cells,and supercapacitors.This article summarizes the structure-performance relationships of electrochemical energy conversion and storage materials(ECSMs)that have been prepared or modified by plasma.It also provides an overview of the challenges and perspectives of plasma technology,which could lead to a new approach for designing and modifying electrode materials in ECSMs. 展开更多
关键词 ELECTROCATALYSTS energy conversion and storage NANOMATERIALS plasma
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Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle
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作者 Yuhao Peng Yuefeng Song +4 位作者 Ihar Razanau Juanxiu Xiao Wei Xiao Di Hu Guoxiong Wang 《Journal of Energy Chemistry》 2025年第1期286-308,共23页
Methane, an abundant one-carbon(C_(1)) resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and ca... Methane, an abundant one-carbon(C_(1)) resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO_(2)emissions and coke deposition. Electrochemical conversion of methane(ECM) using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO_(2)emission. 展开更多
关键词 METHANE Electrochemical conversion Reaction mechanism Catalyst design ELECTRODE ELECTROCATALYSIS
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Anti-Swelling Polyelectrolyte Hydrogel with Submillimeter Lateral Confinement for Osmotic Energy Conversion
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作者 Yongxu Liu Jiangnan Song +10 位作者 Zhen Liu Jialin Chen Dejuan Wang Hui Zhi Jiebin Tang Yafang Zhang Ningbo Li Weijia Zhou Meng An Hong Liu Guobin Xue 《Nano-Micro Letters》 2025年第4期96-110,共15页
Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power densi... Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power density with improved trade-off between membrane permeability and selectivity.Herein,polyelectrolyte hydrogels(channel width,2.2 nm)with inherent high ion conductivity have been demonstrated to enable excellent selective ion transfer when confined in cylindrical anodized aluminum pore with lateral size even up to the submillimeter scale(radius,0.1 mm).The membrane permeability of the anti-swelling hydrogel can also be further increased with cellulose nanofibers.With real seawater and river water,the output power density of a three-chamber cell on behalf of repeat unit of RED system can reach up to 8.99 W m^(-2)(per unit total membrane area),much better than state-of-the-art membranes.This work provides a new strategy for the preparation of polyelectrolyte hydrogel-based ion-selective membranes,owning broad application prospects in the fields of osmotic energy collection,electrodialysis,flow battery and so on. 展开更多
关键词 Ionic polymer HYDROGEL Confinement effect Anti-swelling Osmotic energy conversion
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Established conversions for hybrid entangled states assisted by error-predicted parity-discriminated devices
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作者 Fang-Fang Du Zhi-Guo Fan +2 位作者 Xue-Mei Ren Ming Ma Wen-Yao Liu 《Chinese Physics B》 2025年第1期72-78,共7页
Hybrid entangled states are crucial in quantum physics,offering significant benefits for hybrid quantum communication and quantum computation,and then the conversion of hybrid entangled states is equally critical.This... Hybrid entangled states are crucial in quantum physics,offering significant benefits for hybrid quantum communication and quantum computation,and then the conversion of hybrid entangled states is equally critical.This paper presents two novel schemes,that is,one converts the two-qubit hybrid Knill–Laflamme–Milburn(KLM)entangled state into Bell states and the other one transforms the three-qubit hybrid KLM state into Greenberger–Horne–Zeilinger(GHZ)states assisted by error-predicted and parity-discriminated devices.Importantly,the integration of single photon detectors into the parity-discriminated device enhances predictive capabilities,mitigates potential failures,and facilitates seamless interaction between the nitrogen-vacancy center and photons,so the two protocols operate in an error-predicted way,improving the experimental feasibility.Additionally,our schemes demonstrate robust fidelities(close to 1)and efficiencies,indicating their feasibility with existing technology. 展开更多
关键词 quantum information processing quantum entanglement quantum communication entanglement conversion
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CO hydrogenation conversion driven by micro-environments of active sites over iron carbide catalysts
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作者 Nan Song Xingxing Li +6 位作者 Ebtihal Abograin Wenyao Chen Junbo Cao Jing Zhang De Chen Xuezhi Duan Xinggui Zhou 《Green Energy & Environment》 2025年第2期367-373,共7页
Essentially clearing the structure-activity relationship between iron carbide catalysts involving multiple active centers to understand the reaction mechanism of CO hydrogenation conversion process is still a great ch... Essentially clearing the structure-activity relationship between iron carbide catalysts involving multiple active centers to understand the reaction mechanism of CO hydrogenation conversion process is still a great challenge.Here,two main micro-environment factors,namely electronic properties and geometrical effects were found to have an integrated effect on the mechanism of CO hydrogenation conversion,involving active sites on multiple crystal phases.The Bader charge of the surface Fe atoms on the active sites had a guiding effect on the CO activation pathway,while the spatial configuration of the active sites greatly affected the energy barriers of CO activation.Although the defective surfaces were more conducive to CO activation,the defective sites were not the only sites to dissociate CO,as CO always tended to dissociate in a wider area.This synergistic effect of the micro-environment also occurred during the CO conversion process.Surface C atoms on relatively flat configurations were more likely to form methane,while the electronic properties of the active sites could effectively describe the C-C coupling process,as well as distinguish the coupling mechanisms. 展开更多
关键词 MICRO-ENVIRONMENT CO hydrogenation conversion Electronic property Local environment Synergistic effect
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Insights into reaction mechanisms:Water's role in enhancing in-situ hydrogen production from methane conversion in sandstone
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作者 Keju Yan Krishna Prasad Shrestha +1 位作者 Mohamed Amine Ifticene Qingwang Yuan 《Journal of Energy Chemistry》 2025年第3期353-364,共12页
In-situ conversion of subsurface hydrocarbons via electromagnetic(EM)heating has emerged as a promising technology for producing carbon-zero and affordable hydrogen(H_(2))directly from natural gas reservoirs.However,t... In-situ conversion of subsurface hydrocarbons via electromagnetic(EM)heating has emerged as a promising technology for producing carbon-zero and affordable hydrogen(H_(2))directly from natural gas reservoirs.However,the reaction pathways and role of water as an additional hydrogen donor in EM-assisted methane-to-hydrogen(CH_(4)-to-H_(2))conversion are poorly understood.Herein,we employ a combination of lab-scale EM-heating experiments and reaction modeling analyses to unravel reaction pathways and elucidate water's role in enhancing hydrogen production.The labelled hydrogen isotope of deuterium oxide(D_(2)O)is used to trace the sources of hydrogen.The results show that water significantly boosts hydrogen yield via coke gasification at around 400℃and steam methane reforming(SMR)reaction at over 600℃in the presence of sandstone.Water-gas shift reaction exhibits a minor impact on this enhancement.Reaction mechanism analyses reveal that the involvement of water can initiate auto-catalytic loop reactions with methane,which not only generates extra hydrogen but also produces OH radicals that enhance the reactants'reactivity.This work provides crucial insights into the reaction mechanisms involved in water-carbon-methane interactions and underscores water's potential as a hydrogen donor for in-situ hydrogen production from natural gas reservoirs.It also addresses the challenges related to carbon deposition and in-situ catalyst regeneration during EM heating,thus derisking this technology and laying a foundation for future pilots. 展开更多
关键词 In-situ hydrogen production Water enhancement Methane-to-hydrogen conversion Reaction mechanism Electromagnetic heating
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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni_(2)P for lithium-sulfur batteries
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作者 Lin Peng Yu Bai +3 位作者 Hang Li Meixiu Qu Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》 2025年第1期760-769,共10页
Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish ... Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox dynamics.Herein,we supply a strategy to optimize the electron structure of Ni_(2)P by concurrently introducing B-doped atoms and P vacancies in Ni_(2)P (Vp-B-Ni_(2)P),thereby enhancing the bidirectional sulfur conversion.The study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni_(2)P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides (LiPSs) as well as expediting the bidirectional conversion kinetics of sulfur species.Meanwhile,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni_(2)P selectively promotes Li2S dissolution and nucleation processes.Thus,the Li-S batteries with Vp-B-Ni_(2)P-separators present outstanding rate ability of 777 m A h g^(-1)at 5 C and high areal capacity of 8.03 mA h cm^(-2)under E/S of 5μL mg^(-1)and sulfur loading of 7.20 mg cm^(-2).This work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion. 展开更多
关键词 B-doped atoms P vacancies Nickel phosphide Bidirectional sulfur conversion Lithium-sulfur batteries
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Declining suitability for conversion of drylands to paddy fields in Northeast China:Impact of future climate and socio-economic changes
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作者 Jiacheng Qian Huafu Zhao +5 位作者 Xiaoxiao Wang Tao Wang Zhe Feng Congjie Cao Xiao Li Aihui Zhang 《Geography and Sustainability》 2025年第1期197-210,共14页
Conversion of dryland to paddy fields(CDPF)is an effective way to transition from rain-fed to irrigated agricul ture,helping to mitigate the effects of climate change on agriculture and increase yields to meet growing... Conversion of dryland to paddy fields(CDPF)is an effective way to transition from rain-fed to irrigated agricul ture,helping to mitigate the effects of climate change on agriculture and increase yields to meet growing food demand.However,the suitability of CDPF is spatio-temporally dynamic but has often been neglected in previous studies.To fill this knowledge gap,this research developed a novel method for quantifying the suitability of CDPF,based on the MaxEnt model for application in Northeast China.We explored the spatiotemporal characteristics of the suitability of CDPF under the baseline scenario(2010-2020),and future projections(2030-2090)coupled with climate change and socioeconomic development scenarios(SSP126,SSP245,and SSP585),and revealed the driving factors behind it.Based on this,we identified potential priority areas for future CDPF implementation.The results show that the suitability of CDPF projects implemented in the past ten years is relatively high.Com pared with the baseline scenario,the suitability of CDPF under the future scenarios will decline overall,with the lightest decrease in the RCP585 and the most severe decrease in the RCP245.The key drivers affecting the suitability of CDPF are elevation,slope,population count,total nitrogen,soil organic carbon content,and precip itation seasonality.The potential priority areas for the future CDPF range from 6,284.61 km^(2)to 37,006.02 km^(2).These findings demonstrate the challenges of CDPF in adapting to climate change and food security,and provide insights for food-producing regions around the world facing climate crises. 展开更多
关键词 Cropland conversion Food security SUITABILITY Climate change Machine learning model Northeast China
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Tuning the nucleation kinetics of phosphate chemical conversion coating on Mg-Gd-Y-Zr magnesium alloy:The effect of pretreatment and organic additive
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作者 Siyu Sun Peng Zhou +5 位作者 Yan Chenc JinTao Xiao Jingli Sun Yong Yuan Tao Zhang Fuhui Wang 《Journal of Magnesium and Alloys》 2025年第1期207-218,共12页
In order to obtain a more protective phosphate conversion coating with a denser architecture,the nucleation kinetics of phosphate chemical conversion coating on Mg-Gd-Y-Zr magnesium alloy was tuned in this work.A pret... In order to obtain a more protective phosphate conversion coating with a denser architecture,the nucleation kinetics of phosphate chemical conversion coating on Mg-Gd-Y-Zr magnesium alloy was tuned in this work.A pretreatment process was proposed and organic additives were incorporated,which aims at increasing the ionic produce(J_(sp))at the interface for increasingσ,and decreasing the critical ionic product(J_(C,sp)),respectively.Results prove that the pretreatment of bare alloys in a phosphate bath could increase the ion products of MgHPO_(4)/MnHPO_(4).The addition of benzalkonium chloride could neutralize the charges of crystals,and in turn promote the nucleation kinetics.A denser and more protective conversion coating could consequently be obtained. 展开更多
关键词 Phosphate conversion coating Nucleus density TA/pH theory Magnesium alloy Corrosion resistance
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Quadruple therapy with immunotherapy and chemotherapy as firstline conversion treatment for unresectable advanced gastric adenocarcinoma: A case report
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作者 Xiao-Yu Du Ren-Jie Xia +9 位作者 Li-Wen Shen Jian-Guo Ma Wei-Qing Yao Wei Xu Zhi-Peng Lin Liang-Bin Ma Guo-Qiang Niu Rui-Fang Fan Shu-Mei Xu Long Yan 《World Journal of Gastrointestinal Oncology》 2025年第4期503-514,共12页
BACKGROUND The treatment of gastric cancer remains highly challenging,particularly in cases of unresectable locally advanced or metastatic disease.Although chemotherapy and immunotherapy have shown some efficacy in su... BACKGROUND The treatment of gastric cancer remains highly challenging,particularly in cases of unresectable locally advanced or metastatic disease.Although chemotherapy and immunotherapy have shown some efficacy in such patients,significant limitations persist in extending survival and enhancing safety.To address these challenges,we designed an innovative first-line quadruple conversion therapy regimen that integrates a programmed cell death protein 1(PD-1)inhibitor with chemotherapy,and we successfully implemented this therapy regimen in the treatment of a patient with unresectable locally advanced gastric adenocarcinoma.CASE SUMMARY We report the case of a 55-year-old male who was diagnosed with unresectable locally advanced gastric adenocarcinoma and presented with intermittent epigastric pain and multiple lymph node metastases in the abdominal cavity,with the metastasis being notably large in size.The tumor tissue was negative for human epidermal growth factor receptor 2 by immunohistochemistry.Considering the patient's status,the multidisciplinary team decided to administer sintilimab in combination with albumin-bound paclitaxel(nab-paclitaxel),S-1,and oxaliplatin as a quadruple drug conversion therapy.After 4 cycles of conversion therapy,the patient's epigastric pain was significantly alleviated,his stool color normalized,the volume of the primary tumor and lymph node metastases was markedly reduced,and the tumor marker levels decreased to within the normal range.The patient subsequently underwent laparoscopic total gastrectomy with abdominal lymph node dissection,and postoperative pathological biopsy revealed a pathological complete response and R0 resection,after which the patient recovered to an excellent physical status.CONCLUSION To the best of our knowledge,this is the first reported case of unresectable locally advanced gastric adenocar-cinoma successfully treated with quadruple therapy with a PD-1 inhibitor and chemotherapy as a first-line conversion regimen.This first-line conversion therapy with the quadruple regimen may be effective and safe for unresectable locally advanced gastric adenocarcinoma. 展开更多
关键词 Unresectable locally advanced gastric adenocarcinoma conversion therapy IMMUNOTHERAPY Programmed cell death protein 1 inhibitors Sintilimab Case report
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Combination therapy strategy based on selective internal radiation therapy as conversion therapy for inoperable giant hepatocellular carcinoma:A case report
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作者 Ming-Zhi Hao Hai-Lan Lin +8 位作者 Yu-Bin Hu Qi-Zhong Chen Zhang-Xian Chen Lin-Bin Qiu Duan-Yu Lin Hui Zhang De-Chun Zheng Zhu-Ting Fang Jing-Feng Liu 《World Journal of Gastrointestinal Oncology》 2025年第3期410-417,共8页
BACKGROUND Hepatocellular carcinoma(HCC)has become a growing health concern globally.Microvascular invasion and high tumor burden are key factors limiting the curative effect of selective internal radiation therapy(SI... BACKGROUND Hepatocellular carcinoma(HCC)has become a growing health concern globally.Microvascular invasion and high tumor burden are key factors limiting the curative effect of selective internal radiation therapy(SIRT).CASE SUMMARY This case study reports a 49-year-old woman who was diagnosed with China Liver Cancer Staging(CNLC)IIIa HCC and>15 cm tumor diameter.Initially,due to insufficient future liver remnant and vascular invasion,the tumor was unresectable;however,radical hepatectomy was performed after successful conversion therapy with SIRT using yttrium-90(90Y)resin microspheres followed by hepatic arterial infusion chemotherapy(HAIC)with tyrosine kinase inhibitor(TKI)and anti-programmed death-1(PD-1)antibody.SIRT using 90Y resin microspheres was given by the right hepatic artery and chemoembolization was simultaneously performed in the tumor’s feeding vessels from the right diaphragmatic artery.HAIC was followed every three weeks with lenvatinib and tislelizumab.At 4 months post-SIRT,the tumor was downstaged to CNLC Ib and the patient successfully underwent hepatectomy.The histopathological examination of the resected specimen showed extensive necrosis.CONCLUSION This case study provides evidence for an integrated treatment strategy combining SIRT and HAIC with TKI and anti-PD-1 antibodies for patients with large HCC and microvascular invasion.Further confirmatory trials are required in the future. 展开更多
关键词 Selective internal radiation therapy Hepatic arterial infusion chemotherapy Yttrium-90 resin microspheres Hepatocellular carcinoma conversion therapy Case report
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基于改进Converse断裂点模型和加权Voronoi图的区域城镇体系结构研究——以天水市为例 被引量:11
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作者 郭晓东 李莺飞 马利邦 《地域研究与开发》 CSSCI CSCD 北大核心 2017年第6期70-75,共6页
在对Converse断裂点模型进行改进的基础上,通过构建评价指标体系和计算城镇中心性强度,对天水市城镇体系等级结构进行了划分;通过运用加权Voronoi图,划分了城镇影响范围和城镇经济区。研究表明:1)天水市城镇体系等级分化非常明显,可按... 在对Converse断裂点模型进行改进的基础上,通过构建评价指标体系和计算城镇中心性强度,对天水市城镇体系等级结构进行了划分;通过运用加权Voronoi图,划分了城镇影响范围和城镇经济区。研究表明:1)天水市城镇体系等级分化非常明显,可按中心性值的大小分为3个等级,其中一级城镇主要为天水各县区政府所在地;2)基于加权Voronoi图的城镇经济区打破了行政区划界线,更符合区域"城镇-腹地"相互联系和作用的实际;3)城镇影响空间既受城镇综合实力和区位交通条件的影响,也与地形、资源分布以及历史文化等因素密切相关。在天水市东部和南部,城镇空间影响范围明显大于中部和北部地区。 展开更多
关键词 城镇中心性 城镇等级结构 converse断裂点模型 城镇影响空间 天水市
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应用Converse3D设计和实现虚拟校园 被引量:5
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作者 陶健林 王广军 +1 位作者 章健 苏本跃 《安庆师范学院学报(自然科学版)》 2013年第1期62-65,共4页
高等院校合理运用虚拟校园系统,不仅立体展示校园实景信息和校园文化,而且可以更有效地进行学校的组织管理,同时能够提高学校的知名度、增强学校的竞争力。本文以安庆职业技术学院校园为基础,建立三维实景模型,利用Converse3D虚拟漫游平... 高等院校合理运用虚拟校园系统,不仅立体展示校园实景信息和校园文化,而且可以更有效地进行学校的组织管理,同时能够提高学校的知名度、增强学校的竞争力。本文以安庆职业技术学院校园为基础,建立三维实景模型,利用Converse3D虚拟漫游平台,建立虚拟校园系统,实现实时交互式漫游。 展开更多
关键词 虚拟校园 漫游 三维实景模型 converse3D 实时交互式
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Strong Converse Inequalities for Certain Mixed Szász-Beta Operators 被引量:2
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作者 QI Qiu-lan ZHANG Yu-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期152-158,共7页
In this paper,a strong converse inequality of type B in terms of a new Kfunctional Kλα f,t2(0 < α < 2,0 ≤λ≤ 1) for certain mixed Szász-Beta operators is given.By this inequality,the converse theorem c... In this paper,a strong converse inequality of type B in terms of a new Kfunctional Kλα f,t2(0 < α < 2,0 ≤λ≤ 1) for certain mixed Szász-Beta operators is given.By this inequality,the converse theorem can be obtained for the operators. 展开更多
关键词 Szász-Beta operators K-FUNCTIONAL strong converse inequality Hlder inequality
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Strong Converse Inequalities for Szasz-Mirakjan Operators with Weights 被引量:5
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作者 LIU Guo-jun XUE Yin-chuan SUN Wei-bin 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期384-389,共6页
In this paper, we give the strong converse inequalities of type B with the new K-functional Kλα(f,t2)w(0 ≤λ≤ 1, 0 < α < 2) on weighted approximation for Sz′asz-Mirakjan operators, which extend the previou... In this paper, we give the strong converse inequalities of type B with the new K-functional Kλα(f,t2)w(0 ≤λ≤ 1, 0 < α < 2) on weighted approximation for Sz′asz-Mirakjan operators, which extend the previous results. 展开更多
关键词 Szasz-Mirakjan operators strong converse inequalities APPROXIMATION
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Chloromycetin resistance of clinically isolated E coli is conversed by using EGS technique to repress the Chloromycetin acetyl transferase 被引量:3
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作者 Mei-Ying Gao Chuan-Rui Xu +2 位作者 RU Chen Shou-Gui Liu Jiang-Nan Feng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第46期7368-7373,共6页
AIM: To explore the possibility of repression of chloromycetin (Cm) acyl transferase by using external guided sequence (EGS) in order to converse the clinical E coli isolates from Cm- resistant to Cm- sensitive. ... AIM: To explore the possibility of repression of chloromycetin (Cm) acyl transferase by using external guided sequence (EGS) in order to converse the clinical E coli isolates from Cm- resistant to Cm- sensitive. METHODS: EGS directed against chloromycetin acetyl transferase gene (cat) was cloned to vector pEGFP-C1 which contains the kanamycin (Kin) resistance gene. The recombinant plasmid pEGFP-C1+EGScatl+cat2 was constructed and the blank vector without EGS fragment was used as control plasmids. By using the CaCl2 transformation method, the recombinant plasmids were introduced into the clinically isolated Cm resistant but Km sensitive E coli strains. Transformants were screened on LB agar plates containing Kin. Extraction of plasmids and PCR were applied to identify the positive clones. The growth curve of EGS transformed bacteria cultured in broth with Cm resistance was determined by using spectrophotometer at A600. Drug sensitivity was tested in solid culture containing Cm by using KB method. RESULTS: Transformation studies were carried out on 16 clinically isolated Cm-resistant (250 μg/mL of Cm) E colistrains by using pEGFP-C1-EGScatlcat2 recombinant plasmid. Transformants were screened on LB-agar plates containing Km after the transformation using EGS. Of the 16 tested strains, 4 strains were transformed successfully. Transformants with EGS plasmid showed growth inhibition when grown in liquid broth culture containing 200 μg/mL of Cm. In drug sensitivity test, these strains were sensitive to Cm on LB-agar plates containing 200 μg/mL of Cm. Extraction of plasmids and PCR amplification showed the existence of EGS plasmids in these four transformed strains. These results indicated that the Cat of the four clinical isolates had been suppressed and the four strains were converted to Cm sensitive ones. CONCLUSION: The EGS directed against Cat is able to inhibit the expression of Cat, and hence convert Cm- resistant bacteria to Cm-sensitive ones. Thus, the EGS has the capability of converting the phenotype of clinical drug-resistant isolates strains to drug-sensitive ones. 展开更多
关键词 External guide sequence Drug-resistant bacteria conversion of drug resistance
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STRONG CONVERSE INEQUALITY FOR SZASZ-DURRMEYER OPERATORS 被引量:1
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作者 LI SONG(Department of Applied Mathematics,Zhejiang University, Hangzhou 310027.) 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第3期361-368,共8页
For Szasz-Durrmeyer operators L.(f,x),1<p ∞ we prove that, forsome m,where(x)2=x,M>0,is Ditzian-Totik modulus of smoothness.
关键词 Szasz-Durrmeyer operators strong converse inequality Ditzian-Totik modulus of smoothness.
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Enabling heterogeneous catalysis to achieve carbon neutrality: Directional catalytic conversion of CO_(2) into carboxylic acids 被引量:8
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作者 Xiaofei Zhang Wenhuan Huang +4 位作者 Le Yu Max García-Melchor Dingsheng Wang Linjie Zhi Huabin Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期1-35,共35页
The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving c... The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs. 展开更多
关键词 carbon neutrality carboxylic acids CO_(2)conversion heterogeneous catalyst in situ technology
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