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Nitrogen-doped hierarchical porous carbon from polyaniline/silica self-aggregates for supercapacitor 被引量:3
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作者 peipei li Dazhi Zhang +3 位作者 Yunhui Xu Caihua Ni Gang Shi Xinxin Sang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第3期709-716,共8页
In this paper, nitrogen-doped hierarchical porous carbon(N-HPC) was prepared from polyaniline(PANI)/silica self-aggregates. H-bonding between N\\H groups in aniline/PANI and \\OH groups in nano silica template led to ... In this paper, nitrogen-doped hierarchical porous carbon(N-HPC) was prepared from polyaniline(PANI)/silica self-aggregates. H-bonding between N\\H groups in aniline/PANI and \\OH groups in nano silica template led to a self-assembly type, which enabled the formation of uniform N-HPC nanoparticles. Silica self-aggregates provided macroporous channels resulted in a decreased diffusion distance. After removing the hard template,the N-HPC had a high surface area(899 m^2·g^(-1)). Owing to two co-existed synergetic energy-storage mechanisms and the hierarchical porous structure, the obtained N-HPC exhibited a high specific capacitance of 218.75 F·g^(-1) at 0.5 A·g^(-1), compared with the nonporous nitrogen-doped carbon(N-C) derived from pure PANI. Moreover, the N-HPC electrode demonstrated excellent cycle life, retaining 99% of its initial specific capacitance after 1000 cycles. 展开更多
关键词 NITROGEN-DOPED Hierarchical porous carbon Hard TEMPLATE SILICA self-aggregates
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Computer English Acquisition Environment Construction Based on Question Answering Technology Based on Question Answering Technology
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作者 Fei Lang peipei li +1 位作者 Jian Kang Guanglu Sun 《国际计算机前沿大会会议论文集》 2016年第2期3-5,共3页
In-depth vocabulary knowledge plays a key role in L2(second language)vocabulary acquisition,and computer English vocabulary is vital to academic performances of students majored in Computer Science.While many Chinese ... In-depth vocabulary knowledge plays a key role in L2(second language)vocabulary acquisition,and computer English vocabulary is vital to academic performances of students majored in Computer Science.While many Chinese students cannot realize computer English vocabulary acquisition due to lacking input environment of computer English.To solve this problem,with techniques of keyword search,information retrieval,and text classification,to meet the diverse learning needs of students,it built the in-depth computer English vocabulary knowledge acquisition environment for the high frequency of computer English words,providing the depth of knowledge such as polysemy,synonyms,syntax,and pragmatics.The construction of in-depth computer English vocabulary acquisition environment helps future studies on computer English teaching applications. 展开更多
关键词 Computer English In-depth VOCABULARY knowledge Information RETRIEVAL Text classification
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Computer English Teaching Based on WeChat
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作者 Fei Lang Kexin Zhang +1 位作者 peipei li Guanglu Sun 《国际计算机前沿大会会议论文集》 2016年第2期6-7,共2页
Computer English plays a vital role in academic study for students majored in Computer Science.As the fast development of information technology,traditional English teaching methods cannot meet students’learning need... Computer English plays a vital role in academic study for students majored in Computer Science.As the fast development of information technology,traditional English teaching methods cannot meet students’learning needs.WeChat is the most popular mobile application of social networks in China.Its features of real-time communication,interactivity and utilization of fragmentary time attract educators’attention to its application in teaching.This paper carried out an empirical study to explore applying WeChat in Computer English teaching.With WeChat,an English interaction environment was built,and interactive learning activities were implemented.The experimental results show teaching based on WeChat is effective to improve students’Computer English skills. 展开更多
关键词 COMPUTER ENGLISH WeChat SOCIAL NETWORKS ENGLISH TEACHING
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Mitochondrial Regulation of Macrophages in Innate Immunity and Diverse Roles of Macrophages During Cochlear Inflammation
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作者 Yuan Zhang Fanglei Ye +8 位作者 Xiaolong Fu Shen li Le Wang Yutian Chen Hongmin li Shaojuan Hao Kun Zhao Qi Feng peipei li 《Neuroscience Bulletin》 SCIE CAS CSCD 2024年第2期255-267,共13页
Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation.Mitochondria regulate macrophage activation and innate immun... Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation.Mitochondria regulate macrophage activation and innate immune responses in various inflammatory diseases,including cochlear inflammation.The distribution,number,and morphological characteristics of cochlear macrophages change significantly across different inner ear regions under various pathological conditions,including noise exposure,ototoxicity,and age-related degeneration.However,the exact mechanism underlying the role of mitochondria in macrophages in auditory function remains unclear.Here,we summarize the major factors and mitochondrial signaling pathways(e.g.,metabolism,mitochondrial reactive oxygen species,mitochondrial DNA,and the inflammasome)that influence macrophage activation in the innate immune response.In particular,we focus on the properties of cochlear macrophages,activated signaling pathways,and the secretion of inflammatory cytokines after acoustic injury.We hope this review will provide new perspectives and a basis for future research on cochlear inflammation. 展开更多
关键词 MACROPHAGE MITOCHONDRIA Innate immunity COCHLEA Infammation
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Long-term fallowing produces specific fungal taxa associated with soil carbon storage
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作者 Fang li lin CHEN +5 位作者 Yue li Yanlai HAN Yi WANG peipei li Shuiqing ZHANG Jiabao ZHANG 《Pedosphere》 CSCD 2024年第6期1014-1025,共12页
Cropland expansion has caused the loss of soil organic carbon(SOC)and the degradation of microbial communities.Fallowing is an important strategy for soil restoration,and fungi are critical in soil fertilization.This ... Cropland expansion has caused the loss of soil organic carbon(SOC)and the degradation of microbial communities.Fallowing is an important strategy for soil restoration,and fungi are critical in soil fertilization.This study compared the soil properties and fungal assemblage in two adjacent environments(farmland vs.fallowing)using a 30-year field experiment composed of five treatments:fallowing and agricultural management under no fertilization,chemical fertilization,and chemical fertilization plus cow manure or crop straw.The fallowed soil had more diverse fungi and maintained higher SOC than the artificially managed treatments.Importantly,the relative abundance of Chaetomiaceae was positively correlated with all the carbon components(SOC,dissolved organic carbon,and microbial biomass carbon)simultaneously.An RNA-Seq of Trichocladium uniseriatum,the key fungus affiliated with Chaetomiaceae,showed that straw addition significantly upregulated the genes for T.uniseriatum melanogenesis,resulting in recalcitrant necromass formation.A remarkable carbon dioxide(CO_(2))assimilation capacity of T.uniseriatum was revealed using^(13)C-labelling assay.Therefore,T.uniseriatum improved SOC storage directly by CO_(2)fixation and indirectly by melanogenesis.Fertilization of agricultural systems can stimulate the growth of T.uniseriatum.Inoculation of T.uniseriatum promoted crop growth,facilitating carbon absorption from the roots.This study highlights that the valuable microbial species resources preserved in fallowed soils can improve farmland ecosystems. 展开更多
关键词 ^(13)C-labelling assay Chaetomiaceae CO_(2)fixation long-term fertilization microbial species resources soil fungal community soil organic C Trichocladium
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Pictures of stroke and cerebral vasculature:novel insights and detailed visualisation of U-shaped elastin distribution and disorganised fibre arrangement at carotid bifurcations by advanced techniques
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作者 Shen li peipei li +2 位作者 Xin Wang Zongping Xia Yuming Xu 《Stroke & Vascular Neurology》 2025年第2期276-277,共2页
The bifurcation regions of intracranial and extracranial arteries are common sites for atherosclerosis,predisposing to ischaemic stroke.1 Previous studies have shown that the unique haemodynamics at the bifurca-tion m... The bifurcation regions of intracranial and extracranial arteries are common sites for atherosclerosis,predisposing to ischaemic stroke.1 Previous studies have shown that the unique haemodynamics at the bifurca-tion may lead to alterations in genes and proteins in this region.2 Elastin is closely associated with the progression of athero-sclerosis.3 However,under physiological conditions,the expression and distribu-tion of elastin in bifurcation regions have not yet been elucidated.Mice are the most frequently used animal model for studying atherosclerosis.This study focuses on carotid bifurcation,optimising the iDISCO(immunolabeling-enabled three-dimensional imaging of solvent-cleared organs)technique for whole tissue clearing and staining of the carotid artery in mice.4 These techniques,along with fluorescence micro-optical sectioning tomography(FMOST)technology,have also been used in studies on ischaemic stroke and kidney diseases,4 highlighting their potential for broader applications due to their high precision and three-dimensional imaging capabilities.5 Using FMOST technology in vitro,we have made a detailed visualisation of a U-shaped expression pattern of elastin at bifurcation regions for the first time.Specifically,elastin expression is found to be lowest at the bifurcation itself compared with the regions adjacent to or proximal to the bifurcation(figures 1A,B).Further-more,we observed disorganised arrange-ment of elastic fibres within the bifurcation zone(figures 1C,D).These findings provide important evidence linking elastic fibres to the pathogenesis of atherosclerosis at bifurcations and suggest the potential for more precise local therapies for athero-sclerosis,which could significantly advance precision medicine and reduce the poten-tial side effects on normal tissues. 展开更多
关键词 alterations genes proteins intracranial extracranial arteries cerebral vasculature u shaped elastin distribution ischaemic stroke bifurcation regions disorganised fibre arrangement carotid bifurcations
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Cannabidiol alleviates methamphetamine addiction via targeting ATP5A1 and modulating the ATP-ADO-A1R signaling pathway
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作者 Sha Jin Cong lin +8 位作者 peipei li Xue Wang Yibo Wang Cong Zhang Xuenan Wang Yinghua Peng Haohong li Yuyuan Lu Xiaohui Wang 《Acta Pharmaceutica Sinica B》 2025年第10期5261-5276,共16页
Cannabidiol(CBD),a non-psychoactive cannabinoid,shows great promise in treating methamphetamine(METH)addiction.Nonetheless,the molecular target and the mechanism through which CBD treats METH addiction remain unexplor... Cannabidiol(CBD),a non-psychoactive cannabinoid,shows great promise in treating methamphetamine(METH)addiction.Nonetheless,the molecular target and the mechanism through which CBD treats METH addiction remain unexplored.Herein,CBD was shown to counteract METH-induced locomotor sensitization and conditioned place preference.Additionally,CBD mitigated the adverse effects of METH,such as cristae loss,a decline in ATP content,and a reduction in membrane potential.Employing an activity-based protein profiling approach,a target fishing strategy was used to uncover CBD's direct target.ATP5A1,a subunit of ATP synthase,was identified and validated as a CBD target.Moreover,CBD demonstrated the ability to ameliorate METH-induced ubiquitination of ATP5A1 via the D376 residue,thereby reversing the METH-induced reduction of ATP5A1 and promoting the assembly of ATP synthase.Pharmacological inhibition of the ATP efflux channel pannexin 1,blockade of ATP hydrolysis by a CD39 inhibitor,and blocking the adenosine A1 receptor(A1R)all attenuated the therapeutic benefits of CBD in mitigating METH-induced behavioral sensitization and CPP.Moreover,the RNA interference of ATP5A1 in the ventral tegmental area resulted in the reversal of CBD's therapeutic efficacy against METH addiction.Collectively,these data show that ATP5A1 is a target for CBD to inhibit METH-induced addiction behaviors through the ADO-A1R signaling pathway. 展开更多
关键词 CANNABIDIOL METHAMPHETAMINE ADDICTION MITOCHONDRIA ATP5A1 ATP synthetase Adenosine triphosphate Adenosine A1 receptor
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Comprehensive review of the vascular niche in regulating liver regeneration,fibrosis,and hepatocellular carcinoma
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作者 Yutian Chen Yangfan Zhou +1 位作者 peipei li Bi-Sen Ding 《EngMedicine》 2025年第2期34-40,共7页
The liver serves as a crucial regulatory center in the human body,orchestrating various essential physiological processes and maintaining homeostasis.This organ is heterogeneous,consisting of hepatocytes,liver sinusoi... The liver serves as a crucial regulatory center in the human body,orchestrating various essential physiological processes and maintaining homeostasis.This organ is heterogeneous,consisting of hepatocytes,liver sinusoidal endothelial cells,hepatic stellate cells,and Kupffer cells.These cells are intricately linked in structure and communicate via autocrine and paracrine signaling,playing key roles in the regulation of liver regeneration and fibrosis following injury.In this review,we provide a brief overview of the different cell types within the vascular niche.Moreover,we discuss some of the molecular mechanisms within this niche that guide liver regeneration and fibrosis,as well as hepatocellular carcinoma.It is important to highlight that developing new treatments for liver diseases necessitates a comprehensive understanding of these cellular and molecular mechanisms. 展开更多
关键词 Vascular niche Liver regeneration Liver fibrosis Hepatocellular carcinoma
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An Organic Solvent-Assisted Intercalation and Collection (OAIC) for Ti_(3)C_(2)T_(x) MXene with Controllable Sizes and Improved Yield 被引量:6
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作者 Danyao Qu Yingying Jian +11 位作者 lihao Guo Chen Su Ning Tang Xingmao Zhang Wenwen Hu Zheng Wang Zhenhuan Zhao Peng Zhong peipei li Tao Du Hossam Haick Weiwei Wu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第11期428-440,共13页
A good method of synthesizing Ti_(3)C_(2)T_(x)(MXene)is critical for ensuring its success in practical applications,e.g.,electromagnetic interference shielding,electrochemical energy storage,catalysis,sensors,and biom... A good method of synthesizing Ti_(3)C_(2)T_(x)(MXene)is critical for ensuring its success in practical applications,e.g.,electromagnetic interference shielding,electrochemical energy storage,catalysis,sensors,and biomedicine.The main concerns focus on the moderation of the approach,yield,and product quality.Herein,a modified approach,organic solvent-assisted intercalation and collection,was developed to prepare Ti_(3)C_(2)T_(x) flakes.The new approach simultaneously solves all the concerns,featuring a low requirement for facility(centrifugation speed<4000 rpm in whole process),gram-level preparation with remarkable yield(46.3%),a good electrical conductivity(8672 S cm^(−1)),an outstanding capacitive performance(352 F g^(−1)),and easy control over the dimension of Ti_(3)C_(2)T_(x) flakes(0.47–4.60μm^(2)).This approach not only gives a superb example for the synthesis of other MXene materials in laboratory,but sheds new light for the future mass production of Ti_(3)C_(2)T_(x) MXene. 展开更多
关键词 Two-dimensional materials MXenes Controllable sizes High yield
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Effect of the pineal gland on 5-hydroxytryptamine and γ-aminobutyric acid secretion in the hippocampus of male rats during the summer and winter 被引量:4
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作者 Ting li Hailu Wang +3 位作者 Hewei Zhang Leilei liu peipei li Shuran Ma 《Journal of Traditional Chinese Medical Sciences》 2020年第3期283-290,共8页
Objective:The present study aimed to investigate the effect of seasonal variation on neurotransmitter release in the hippocampus of normal rats and rats with pineal excision.Methods:Two time points,the summer and wint... Objective:The present study aimed to investigate the effect of seasonal variation on neurotransmitter release in the hippocampus of normal rats and rats with pineal excision.Methods:Two time points,the summer and winter solstice,which are the longest and shortest days of the year,respectively,were selected.Male Spraguee Dawley rats that underwent a sham operation without pineal excision were included as a control group.The concentrations of 5-hydroxytryptamine(5-HT)andγ-aminobutyric acid(GABA)were determined by radioimmunoassays and enzyme-linked immunosorbent assays,respectively.Results:In the winter,the 5-HT and GABA levels in normal rats exhibited a significant difference compared with those in the operation group(P<.01).A difference was also noted in GABA levels between the normal group and the sham operation group(P<.05).The concentrations of 5-HT and GABA in the hippocampal tissues of the normal group exhibited a seasonal rhythm consisting of elevation during the summer and reduction during the winter(P<.01),while the GABA levels in the sham operation group exhibited a significant difference,with elevation during the summer and reduction during the winter(P<.01).In the operation group,GABA showed the same trend(P<.01).Conclusion:The seasonal rhythm of neurotransmitter secretion by the hippocampus(5-HT and GABA)consisted of elevation during the summer and reduction during the winter.During the winter,the pineal gland exhibited a reverse regulatory effect on the secretion of 5-HT and GABA in the hippocampus,and it exhibited seasonal selectivity with regard to the regulation of 5-HT. 展开更多
关键词 MELATONIN 5-HYDROXYTRYPTAMINE γ-aminobutyric acid PHOTOPERIOD Rats Seasonal rhythm Pineal excision
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AlEt_(1.5)Cl_(1.5)与Al(OPhCH_3)(i-Bu)_2复配对钼系催化丁二烯聚合和产物微观结构的影响
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作者 张彬彬 李培培 +1 位作者 赵煊 华静 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第3期8-13,共6页
采用MoCl_5·磷酸三丁酯(TBP)/Al(OPhCH_3)(i-Bu)_2和MoCl_5·TBP/AlEt_(1.5)Cl_(1.5)钼系催化体系催化丁二烯(Bd)配位聚合可分别制备高1,2含量的聚丁二烯橡胶(HVPB)和含反式(trans)-1,4-结构的部分结晶的聚丁二烯橡胶。在同一... 采用MoCl_5·磷酸三丁酯(TBP)/Al(OPhCH_3)(i-Bu)_2和MoCl_5·TBP/AlEt_(1.5)Cl_(1.5)钼系催化体系催化丁二烯(Bd)配位聚合可分别制备高1,2含量的聚丁二烯橡胶(HVPB)和含反式(trans)-1,4-结构的部分结晶的聚丁二烯橡胶。在同一反应器中先加入Al(i-Bu)_2(OPhCH_3)/MoCl_5·TBP催化丁二烯聚合,然后单独加入AlEt_(1.5)Cl_(1.5)或同时加入AlEt_(1.5)Cl_(1.5)/MoCl_5·TBP,制备1,2-结构和trans-1,4结构在一定范围内可调的聚丁二烯的立构共混物。文中研究了催化剂的加入方式、第二组分加入时间和聚合温度等对聚合活性和产物结构的影响。实验结果表明,通过2种Al加入量的调节和反应条件的改变可实现1,2-结构含量和trans-1,4-结构含量分别在30%~80%和15%~60%范围内的调节,从而制得含一定结晶微区的无定形1,2-PB,有望提高1,2-PB的力学强度。 展开更多
关键词 钼系催化剂 1 2-聚丁二烯 反式-1 4-聚丁二烯 结晶
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Twenty years of Gendicine?rAd-p53 cancer gene therapy:The first-in-class human cancer gene therapy in the era of personalized oncology 被引量:1
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作者 li Qi Guiqing li +4 位作者 peipei li Hongwei Wang Xiaolong Fang Tongchuan He Jingjing li 《Genes & Diseases》 SCIE CSCD 2024年第4期234-245,共12页
Genetic mutations in TP53 contribute to human malignancies through various means.To date,there have been a variety of therapeutic strategies targeting p53,including gene therapy to restore normal p53 function,mutant p... Genetic mutations in TP53 contribute to human malignancies through various means.To date,there have been a variety of therapeutic strategies targeting p53,including gene therapy to restore normal p53 function,mutant p53 rescue,inhibiting the MDM2-p53 interaction,p53-based vaccines,and a number of other approaches.This review focuses on the functions of TP53 and discusses the aberrant roles of mutant p53 in various types of cancer.Recombinant human p53 adenovirus,trademarked as Gendicine,which is the first anti-tumor gene therapy drug,has made tremendous progress in cancer gene therapy.We herein discuss the biological mechanisms by which Gendicine exerts its effects and describe the clinical re-sponses reported in clinical trials.Notably,the clinical studies suggest that the combination of Gendicine with chemotherapy and/or radiotherapy may produce more pronounced efficacy in slowing tumor growth and progression than gene therapy/chemotherapy alone.Finally,we summarize the methods of administration of recombinant human p53 adenovirus for different cancer types to provide a reference for future clinical trials. 展开更多
关键词 Gendicine Gene therapy p53 mutation Recombinant p53 adenovirus TP53
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High-index faceted jagged PtPdTe nanotubes for methanol oxidation reaction
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作者 Qing Hu peipei li +6 位作者 Mengqian li Jiacong Wu Jinyu Ding Wenya Fan Qinyuan Hu Qingxia Chen Xingchen Jiao 《Science China Chemistry》 2025年第9期4216-4223,共8页
Rationally designing the surface structure with desirable facets has been demonstrated as an effective approach to regulating the catalytic activity and anti-CO poisoning capability of Pd-based catalysts for methanol ... Rationally designing the surface structure with desirable facets has been demonstrated as an effective approach to regulating the catalytic activity and anti-CO poisoning capability of Pd-based catalysts for methanol oxidation reaction(MOR).However,the synthesis of Pd-based alloy with high-index facets to further improve Pd utilization remains a fundamental challenge.Herein,a simple solvothermal method was proposed to synthesize the jagged PtPdTe nanotubes(NTs)with abundant zigzag atomic steps on their surfaces.These zigzag facets are more favorable for both the adsorption of OH and the desorption of CO during MOR.Compared with the smooth PtPdTe NTs,the jagged PtPdTe NTs exhibit an enhanced mass activity of 4201.6 mA mg^(-1) and specific activity of 4.12 mA cm^(-2),which are 6.7 and 3.2 times higher than those of commercial Pd/C catalysts,respectively.This work not only advances the understanding of surface engineering in catalysis but also extends the novel design of highly efficient and durable Pd-based catalysts for fuel cells. 展开更多
关键词 high-index facets JAGGED surface engineering CO desorption MOR
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Arsenic trioxide elicits prophylactic and therapeutic immune responses against solid tumors by inducing necroptosis and ferroptosis 被引量:9
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作者 Jinfeng Chen Ziqi Jin +4 位作者 Shuqing Zhang Xiao Zhang peipei li Heng Yang Yuting Ma 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2023年第1期51-64,共14页
Boosting tumor immunosurveillance with vaccines has been proven to be a feasible and cost-effective strategy to fight cancer. Although major breakthroughs have been achieved in preventative tumor vaccines targeting on... Boosting tumor immunosurveillance with vaccines has been proven to be a feasible and cost-effective strategy to fight cancer. Although major breakthroughs have been achieved in preventative tumor vaccines targeting oncogenic viruses, limited advances have been made in curative vaccines for virus-irrelevant malignancies. Accumulating evidence suggests that preconditioning tumor cells with certain cytotoxic drugs can generate whole-cell tumor vaccines with strong prophylactic activities. However, the immunogenicity of these vaccines is not sufficient to restrain the outgrowth of existing tumors. In this study, we identified arsenic trioxide (ATO) as a wide-spectrum cytotoxic and highly immunogenic drug through multiparameter screening. ATO preconditioning could generate whole-cell tumor vaccines with potent antineoplastic effects in both prophylactic and therapeutic settings. The tumor-preventive or tumor-suppressive benefits of these vaccines relied on CD8^(+) T cells and type I and II interferon signaling and could be linked to the release of immunostimulatory danger molecules. Unexpectedly, following ATO-induced oxidative stress, multiple cell death pathways were activated, including autophagy, apoptosis, necroptosis, and ferroptosis. CRISPR‒Cas9-mediated knockout of cell death executors revealed that the absence of Rip3, Mlkl, or Acsl4 largely abolished the efficacy of ATO-based prophylactic and therapeutic cancer vaccines. This therapeutic failure could be rescued by coadministration of danger molecule analogs. In addition, PD-1 blockade synergistically improved the therapeutic efficacy of ATO-based cancer vaccines by augmenting local IFN-γ production. 展开更多
关键词 Tumor vaccine Arsenic trioxide NECROPTOSIS Ferroptosis IMMUNOSURVEILLANCE
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Breaking the activity limitation of iridium single-atom catalyst in hydrogenation of quinoline with synergistic nanoparticles catalysis 被引量:5
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作者 Qikai Shen Hongqiang Jin +4 位作者 peipei li Xiaohu Yu lirong Zheng Weiguo Song Changyan Cao 《Nano Research》 SCIE EI CSCD 2022年第6期5024-5031,共8页
Single-atom catalysts(SACs)with the advantages of homogeneous and heterogeneous catalysts have become a hot-spot in catalysis field.However,for lack of metal–metal bond in SACs,H_(2)has to go through heterolytic diss... Single-atom catalysts(SACs)with the advantages of homogeneous and heterogeneous catalysts have become a hot-spot in catalysis field.However,for lack of metal–metal bond in SACs,H_(2)has to go through heterolytic dissociation pathway,which has higher barrier than homolytic dissociation pathway,and thus limits the hydrogenation activity of SACs.Herein,we propose and demonstrate through constructing synergistic iridium single atoms and nanoparticles co-existed catalyst(denoted as Ir_(1+NPs)/CMK)to boost the catalytic activity of quinoline hydrogenation.Both experimental and density functional theory calculation results confirm that Ir_(1)single sites activate quinoline,while Ir nanoparticles boost hydrogen dissociation.H atoms generated at Ir nanoparticles migrate to the quinoline bounded Ir_(1)single sites to complete hydrogenation.The Ir_(1+NPs)/CMK catalyst exhibits much higher reactivity with turnover frequency of 7,800 h^(−1)than those counterpart Ir_(1)/CMK and IrNPs/CMK catalysts,and is 20,000 times higher activity of commercial Ir/C benchmark catalyst for hydrogenation of quinoline under the same reaction conditions.This synergistic catalysis strategy between single atoms and nanoparticles provides a solution to further improve the performance of SACs for hydrogenation. 展开更多
关键词 heterogeneous catalysis single atom SYNERGISTIC QUINOLINE HYDROGENATION
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Ionic-liquid-assisted synthesis of metal single-atom catalysts for benzene oxidation to phenol 被引量:4
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作者 Qikai Shen peipei li +8 位作者 Weiming Chen Hongqiang Jin Jia Yu Lei Zhu Zhucheng Yang Runqing Zhao lirong Zheng Weiguo Song Changyan Cao 《Science China Materials》 SCIE EI CAS CSCD 2022年第1期163-169,共7页
Ionic liquids(ILs)have the advantages of low cost,eco-friendliness,abundant heteroatoms,excellent solubility,and coordinated ability with metal ions.These features make ILs a suitable precursor for fabricating metal s... Ionic liquids(ILs)have the advantages of low cost,eco-friendliness,abundant heteroatoms,excellent solubility,and coordinated ability with metal ions.These features make ILs a suitable precursor for fabricating metal singleatom catalysts(SACs).Herein,we prepared various metal single atoms anchored on ultrathin N-doped nanosheets(denoted as Cu_(1)/NC,Fe_(1)/NC,Co_(1)/NC,Ni_(1)/NC,and Pd_(1)/NC)by direct pyrolysis using ILs and g-C_(3)N_(4)nanosheets as templates.Taking benzene oxidation to phenol with H_(2)O_(2)as a model reaction to evaluate their catalytic performance and potential applications,Cu_(1)/NC calcined at 1000℃(denoted as Cu1/NC-1000)exhibits the highest activity with a turnover frequency of about 200 h^(-1)in the first 1 h at 60℃,which is better than that of most metal SACs reported in the literature.High benzene conversion of 82% with high phenol selectivity of 96% and excellent recyclability were achieved using the Cu_(1)/NC-1000 catalyst.This study provides an efficient general strategy for fabricating SACs using ILs for catalytic applications. 展开更多
关键词 single-atom catalysis copper benzene oxidation ionic liquids
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A survey on online feature selection with streaming features 被引量:4
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作者 Xuegang HU Peng ZHOU +2 位作者 peipei li Jing WANG Xindong WU 《Frontiers of Computer Science》 SCIE EI CSCD 2018年第3期479-493,共15页
In the era of big data, the dimensionality of data is increasing dramatically in many domains. To deal with high dimensionality, online feature selection becomes critical in big data mining. Recently, online selection... In the era of big data, the dimensionality of data is increasing dramatically in many domains. To deal with high dimensionality, online feature selection becomes critical in big data mining. Recently, online selection of dynamic features has received much attention. In situations where features arrive sequentially over time, we need to perform online feature selection upon feature arrivals. Meanwhile, considering grouped features, it is necessary to deal with features arriving by groups. To handle these challenges, some state-of- the-art methods for online feature selection have been proposed. In this paper, we first give a brief review of traditional feature selection approaches. Then we discuss specific problems of online feature selection with feature streams in detail. A comprehensive review of existing online feature selection methods is presented by comparing with each other. Finally, we discuss several open issues in online feature selection. 展开更多
关键词 big data feature selection online feature selection feature stream
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p-Arsanilic acid decontamination over a wide pH range using biochar-supported manganese ferrite material as an effective persulfate catalyst:Performances and mechanisms 被引量:3
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作者 Bin Yao Xia Chen +4 位作者 Kun Zhou Zirui Luo peipei li Zihui Yang Yaoyu Zhou 《Biochar》 SCIE 2022年第1期665-677,共13页
Direct chemical oxidation and pure adsorption could not effectively remove p-Arsanilic acid(p-ASA)and the released inor-ganic arsenic.Herein,one novel biochar supported MnFe_(2)O_(4)(MFB)was synthesized and adopted fo... Direct chemical oxidation and pure adsorption could not effectively remove p-Arsanilic acid(p-ASA)and the released inor-ganic arsenic.Herein,one novel biochar supported MnFe_(2)O_(4)(MFB)was synthesized and adopted for p-ASA degradation and synchronous adsorption of the generated inorganic arsenic.The MFB/persulfate(PS)system could remain effective under a wide pH range(3.0-9.0),and the released arsenic could be removed simultaneously by MFB.Mechanism investiga-tion revealed that the functional groups of MFB(i.e.O-C=O and C=O),Fe and Mn oxides on MFB all contributed to PS activation.O_(2)^(·−)and^(1)O_(2)were the main reactive oxygen species(ROS)responsible for p-ASA degradation,and^(1)O_(2)was the predominant ROS.Besides,the MFB possessed superior reusability.Therefore,it is expected to develop a potential method for organic arsenic contaminants removal via an oxidation-adsorption process,and the results could also shed light on the better understanding of the PS activation mechanisms. 展开更多
关键词 PERSULFATE BIOCHAR Manganese ferrite Redox cycle Organic arsenic compounds
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High linearity U-band power amplifier design:a novel intermodulation point analysis method 被引量:3
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作者 Jie CUI peipei li Weixing SHENG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2023年第1期176-186,共11页
A power amplifier’s linearity determines the emission signal’s quality and the efficiency of the system.Nonlinear distortion can result in system bit error,out-of-band radiation,and interference with other channels,... A power amplifier’s linearity determines the emission signal’s quality and the efficiency of the system.Nonlinear distortion can result in system bit error,out-of-band radiation,and interference with other channels,which severely influence communication system’s quality and reliability.Starting from the third-order intermodulation point of the milimeter wave(mm-Wave)power amplifiers,the circuit’s nonlinearity is compensated for.The analysis,design,and implementation of linear class AB mm-Wave power amplifiers based on GlobalFoundries 45 nm CMOS silicon-on-insulator(SOI)technology are presented.Three single-ended and differential stacked power amplifiers have been implemented based on cascode cells and triple cascode cells operating in U-band frequencies.According to nonlinear analysis and on-wafer measurements,designs based on triple cascode cells outperform those based on cascode cells.Using single-ended measurements,the differential power amplifier achieves a measured peak power-added efficiency(PAE)of 47.2%and a saturated output power(P_(sat))of 25.2 dBm at 44 GHz.The amplifier achieves a P_(sat)higher than 23 dBm and a maximum PAE higher than 25%in the measured bandwidth from 44 GHz to 50 GHz. 展开更多
关键词 CMOS silicon-on-insulator(SOI) Linearity analysis Milimeter wave(mm-Wave) Power amplifier
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Enzyme-free Electrochemical Detection of Hydrogen Peroxide Based on the Three-Dimensional Flower-like Cu-based Metal Organic Frameworks and MXene Nanosheets 被引量:1
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作者 Dan Cheng peipei li +3 位作者 Xiaohua Zhu Meiling liu Youyu Zhang Yang liu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2021年第8期2181-2187,共7页
Cu-based metal organic frameworks(MOFs)are regarded as promising sensing materials,which have abundant metal sites,large surface area and simple synthesis processes.In this work,a novel three-dimensional flower-like C... Cu-based metal organic frameworks(MOFs)are regarded as promising sensing materials,which have abundant metal sites,large surface area and simple synthesis processes.In this work,a novel three-dimensional flower-like Cu-MOF was synthesized,which was combined with ultra-thin MXene nanosheets to construct a novel electrochemical sensor for H_(2)O_(2). 展开更多
关键词 Metal-organic frameworks MXene Enzyme-free SENSORS Hydrogen peroxide
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