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Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis
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作者 jie wang Wei wang +4 位作者 Xuheng Chen Junfang Bao Qiuyue Hao Heng Zheng Runsheng Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期58-69,共12页
The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the micro... The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%. 展开更多
关键词 low-carbon ironmaking iron coke GASIFICATION structural evolution kinetic model
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Pancreatic primitive neuroectodermal tumors:Clinical features,treatment,and influencing factors
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作者 Yan-Fei He Huan-Zhi wang +4 位作者 Xiao-Dong Hu Jun-Qiang Liu Hu-Ming Li jie wang Shuang-Feng Lu 《World Journal of Gastrointestinal Oncology》 2025年第2期230-245,共16页
BACKGROUND Data on clinical characteristics,treatment outcomes,and prognosis of pancreatic primitive neuroectodermal tumors(PNETs)are limited.AIM To analyze the clinical data of 30 patients with pancreatic PNETs to id... BACKGROUND Data on clinical characteristics,treatment outcomes,and prognosis of pancreatic primitive neuroectodermal tumors(PNETs)are limited.AIM To analyze the clinical data of 30 patients with pancreatic PNETs to identify their clinical characteristics and factors associated with prognosis.METHODS We used the keywords"primary neuroectodermal tumor,""digestive tract,""pancreas,""pancreatic,"and"gastrointestinal,"individually or in combination,to collect data from a global database for all patients with pancreatic PNET to date.Univariate and Cox regression analyses were performed to identify prognostic factors for patient survival.RESULTS A total of 30 cases of pancreatic PNET were included in this study:15 males and 15 females with a mean age of 24 years.The main symptom was abdominal pain(73.3%),and the median tumor size was 7.85 cm.Twenty-four patients(80.0%)underwent surgery and nineteen patients received adjuvant therapy.Local metastasis was observed in 13 patients(43.3%),lymph node metastasis in 10 patients(33.3%),and distant metastasis in 6 patients(20.0%).Local recurrence was observed in 13 patients(43.3%).The median survival time of all patients was 29.4 months,and the overall estimated 1-year and 3-year survival rates were approximately 66.0%and 36.4%,respectively.Univariate analysis showed that chemotherapy(P=0.036),local metastasis(P=0.041),lymph node metastasis(P=0.003),distant metastasis(P=0.049),and surgical margins(P=0.048)were the prognostic factors affecting survival.Multivariate analysis revealed only lymph node metastasis(P=0.012)as a prognostic factor.CONCLUSION Pancreatic PNET is extremely rare,occurs in young adults,has no apparent sex predisposition,has a high rate of metastasis and early recurrence,and has a very poor prognosis.The diagnosis of pancreatic PNET requires a combination of clinical symptoms,pathologic features,immunohistochemistry,and cytogenetic analysis.Univariate analysis suggested that chemotherapy,metastasis,and surgical margins were prognostic factors affecting survival,and multivariate analysis suggested that lymph node metastasis is an important prognostic factor.Therefore,early diagnosis,early and extensive resection,and adjuvant chemoradiotherapy may help improve prognosis. 展开更多
关键词 Primitive neuroectodermal tumor PANCREAS SARCOMA DIAGNOSIS PROGNOSIS TREATMENT
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Effect of nalbuphine on analgesia and pain factors after gastric cancer resection
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作者 Jia-Li Qian jie wang +3 位作者 Zi-Yi Shen Bao-Qin Xu Dan-Ping Shen Cheng Yang 《World Journal of Gastrointestinal Surgery》 2025年第1期203-208,共6页
BACKGROUND Gastric cancer(GC)is a prevalent tumor in the digestive system,with around one million new cases reported annually,ranking it as the third most common malignancy.Reducing pain is a key research focus.This s... BACKGROUND Gastric cancer(GC)is a prevalent tumor in the digestive system,with around one million new cases reported annually,ranking it as the third most common malignancy.Reducing pain is a key research focus.This study evaluates the effect of nalbuphine on the analgesic effect and the expression of pain factors in patients after radical resection.AIM To provide a reference for postoperative analgesia methods.METHODS One hundred eight patients with GC,admitted between January 2022 and June 2024,underwent radical gastrectomy.They received a controlled analgesia pump and a transverse abdominis muscle plane block,divided into two groups of 54 patients in each group.The control group received sufentanil,while the observation group received nalbuphine as an analgesic.Postoperative analgesic effects,pain factor expression,and adverse effects were compared.RESULTS The resting pain and activity pain scores in the observation group at 6,12,24 and 48 hours were significantly lower than those in the control group.Additionally,the number of presses and consumption of the observation group at 48 hours were lower than those of the control group;and the response rate of the observation group was higher than that of the control group(P<0.05).The prostaglandin E2,substance P,and serotonin levels 24 hours after the observation group were lower than those in the control group,and the incidence of adverse reactions was 5.56%lower than 22.22%in the control group(P<0.05).CONCLUSION The findings suggest that nalbuphine enhances postoperative multimodal analgesia in patients with radical GC,effectively improving postoperative analgesic effect,relieving postoperative resting and active pain,and reducing postoperative pain factor expression,demonstrating its potential for clinical application. 展开更多
关键词 NALBUPHINE Radical resection of gastric cancer Multimodal analgesia Clinical treatment TUMOR
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ClBBM and ClPLT2 function redundantly during both male and female gametophytes development in watermelon
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作者 Qiyan Liu Dongfen Han +9 位作者 Jinfan Chen jie wang Denghu Cheng Xiner Chen Jiao Jiang Shujuan Tian Jiafa wang Man Liu Haizheng Xiong Li Yuan 《Horticultural Plant Journal》 2025年第1期323-335,共13页
As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and specialization.Gametogenesis has been extensively explored in model plants,b... As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and specialization.Gametogenesis has been extensively explored in model plants,but the regulatory mechanism of gametophyte development largely remains unknown in Cucurbitaceae species.In present study,we have shown that watermelon ClBBM and ClPLT2,two AP2/ERF transcription factors,participated in both male and female gametophyte development.Clbbm and Clplt2 single mutants resembled wild-type phenotypes in both vegetative and reproductive development.But Clbbm/Clplt2 double mutant showed partial pollen abortion and bore less seeds comparing to WT.Our results indicated that the abnormal pollen grains were caused by premature tapetum degeneration,and reduced seed-set was due to faulty embryo sac development.ClBBM and ClPLT2 were expressed in FG4 embryo sacs,and their transcripts were also detectable in the tapetum and microspore of stage 9 anthers,which was consistent with developmental stages of defective phenotypes observed in double mutant.The expression of genes essential for tapetum development,ClATM1,ClAMS,ClMS1 and ClMS188,was decreased in Clbbm/Clplt2 double mutants.Moreover,the transcriptome analysis indicated that ClBBM and ClPLT2 participated in tapetum and pollen wall development by regulate cell cycle,transmembrane transport,glucan and cellulose metabolic process.Collectively,ClBBM and ClPLT2 were functionally redundant in regulating gametophyte development in watermelon,and their functions differ from their homologous genes in model plant Arabidopsis. 展开更多
关键词 WATERMELON GAMETOPHYTE Male sterility SEEDLESS
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“一点两线三面”创新实验平台的构建与实践 被引量:2
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作者 龚良玉 王杰 +6 位作者 杜丰玉 徐鲁斌 马传利 颜世海 宋祖伟 刘福恒 王修中 《大学化学》 CAS 2024年第4期26-32,共7页
传统化学实验室功能单一、分布零散、共享性差,导致实验用房和实验设备利用效率低,这种建设模式不利于多学科知识的交叉融合,一定程度上影响学生综合素质的发展。本研究秉承“建优质平台,抓实践育人,树创新理念,育创新人才”的指导思想... 传统化学实验室功能单一、分布零散、共享性差,导致实验用房和实验设备利用效率低,这种建设模式不利于多学科知识的交叉融合,一定程度上影响学生综合素质的发展。本研究秉承“建优质平台,抓实践育人,树创新理念,育创新人才”的指导思想,在化学实验室资源整合共享、利用率提升、开放式管理以及创新应用型人才培养质量提升等方面积极进行教学改革,经过多年探索,搭建起“以提升学生创新实践能力为着力点”“教学科研两条主线”“教学科研三层面”的创新实验(训)平台,取得了一定成效,将为同类高校的创新实验(训)平台建设提供参考。 展开更多
关键词 创新型 应用型 一点两线三面 实验(训)平台
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Comparative study on the anti-tuberculous effect and mechanism of the traditional Chinese medicines NiuBeiXiao He extract and JieHeWan 被引量:1
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作者 Li-Yao Duan Yan Liang +10 位作者 Wen-Ping Gong Yong Xue jie Mi jie wang Lan wang Zai-Xing Jia Hong Lei Yu-Mei Liang Jun Liu Yue Zheng Xue-Qiong Wu 《Military Medical Research》 SCIE CSCD 2022年第2期164-183,共20页
Background:The traditional Chinese medicine NiuBeiXiaoHe(NBXH)extract and Chinese medicine preparation JieHeWan(JHW)exhibit anti-tuberculosis(TB)effects.The anti-TB effect of NBXH was compared with that of JHW to eluc... Background:The traditional Chinese medicine NiuBeiXiaoHe(NBXH)extract and Chinese medicine preparation JieHeWan(JHW)exhibit anti-tuberculosis(TB)effects.The anti-TB effect of NBXH was compared with that of JHW to elucidate the mechanism of action of NBXH.Methods:BALB/c mice aged 6-8 weeks were randomly divided into a normal control group,TB model group,JHW treatment group,and NBXH treatment group.After 3 and 13 weeks of treatment,the therapeutic effect in each group was evaluated by comparing lung histopathology,lung and liver colony counts,the number of spots representing effector T cells secreting IFN-γin an enzyme-linked immunospot assay(ELISPOT),and the levels of Th1,Th2,and Th17 cytokines,which were measured by a cytometric bead array(CBA).Mouse RNA samples were subjected to transcriptome sequencing.Results:After 13 weeks of treatment,the mean histopathological lesion area of the NBXH group was significantly smaller than that of the TB model group(P<0.05).Compared with those in the TB model group,the lung colony counts in the JHW and NBXH groups were significantly decreased(P<0.05),and the IL-2 and IL-4 levels in the NBXH group were significantly increased(P<0.05).NBXH partly restored significant changes in gene expression caused by Mycobacterium tuberculosis(M.tuberculosis)infection.According to GO and KEGG analyses,the changes in biological process(BP),cell composition(CC)and molecular function(MF)terms and in signaling pathways caused by NBXH and JHW treatment were not completely consistent,but they were mainly related to the immune response and inflammatory response in the mouse TB model.Conclusions:NBXH had therapeutic effects similar to those of JHW in improving lung histopathology,reducing lung colony counts,and regulating the levels of cytokines.NBXH restored significant changes in gene expression and repaired cell damage caused by M.tuberculosis infection by regulating immune-related pathways,which clarified the mechanism of action of NBXH. 展开更多
关键词 Traditional Chinese medicine TUBERCULOSIS NiuBeiXiaoHe extract JieHeWan Therapeutic effect
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活血化瘀治疗冠脉微循环障碍的研究进展
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作者 王阶 董艳 +4 位作者 熊兴江 刘咏梅 胡骏 陈聪 程嘉雯 《中国科学基金》 CSSCI CSCD 北大核心 2024年第4期677-686,共10页
冠状动脉微循环障碍广泛存在于多种心血管疾病中,与左室重构、心血管事件密切相关。本病病机演变以血瘀为核心,活血化瘀法可改善患者冠状动脉血流储备及微循环阻力指数,对于冠状动脉微循环障碍具有良好的治疗效果。机制方面,活血化瘀诸... 冠状动脉微循环障碍广泛存在于多种心血管疾病中,与左室重构、心血管事件密切相关。本病病机演变以血瘀为核心,活血化瘀法可改善患者冠状动脉血流储备及微循环阻力指数,对于冠状动脉微循环障碍具有良好的治疗效果。机制方面,活血化瘀诸法可调节冠状动脉微血管功能障碍的诸多关键病理生理环节:如,活血化瘀可有效抑制炎症、氧化应激及血栓形成;活血化痰可保护血管内皮;益气活血能改善能量代谢;补肾活血促进血管新生、建立冠脉侧支循环。应用现代科学深入挖掘活血化瘀诸法治疗本病的机制,或为解决本病治疗提供新的思路。 展开更多
关键词 冠脉微循环障碍 中医药 活血化瘀 血瘀证 作用机制
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材料虚拟仿真综合实习课程思政教学设计与实践
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作者 牛永盛 李红春 +3 位作者 王杰 李伟娜 龚良玉 孙钦星 《大学化学》 2024年第12期65-72,共8页
专业课程融入课程思政是高校协同育人的重要举措。材料虚拟仿真综合实习是材料类专业的一门专业综合实践课,采用了沉浸式体验思政案例。本文从实习课程开展课程思政改革的意义和必要性入手,重点介绍了材料虚拟仿真综合实习开展的课程思... 专业课程融入课程思政是高校协同育人的重要举措。材料虚拟仿真综合实习是材料类专业的一门专业综合实践课,采用了沉浸式体验思政案例。本文从实习课程开展课程思政改革的意义和必要性入手,重点介绍了材料虚拟仿真综合实习开展的课程思政教学改革实践,总结了专业实习课程开展思政教学的目标、举措和意义,并对改革成效进行了介绍。 展开更多
关键词 虚拟仿真 课程思政 实践课程 教学改革
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CitationAS: A Tool of Automatic Survey Generation Based on Citation Content 被引量:1
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作者 jie wang chengzhi zhang +1 位作者 mengying zhang sanhong deng 《Journal of Data and Information Science》 CSCD 2018年第2期20-37,共18页
Purpose: This study aims to build an automatic survey generation tool, named CitationAS, based on citation content as represented by the set of citing sentences in the original articles.Design/methodology/approach: ... Purpose: This study aims to build an automatic survey generation tool, named CitationAS, based on citation content as represented by the set of citing sentences in the original articles.Design/methodology/approach: Firstly, we apply LDA to analyse topic distribution of citation content. Secondly, in CitationAS, we use bisecting K-means, Lingo and STC to cluster retrieved citation content. Then Word2Vec, Word Net and combination of them are applied to generate cluster labels. Next, we employ TF-IDF, MMR, as well as considering sentence location information, to extract important sentences, which are used to generate surveys. Finally, we adopt manual evaluation for the generated surveys.Findings: In experiments, we choose 20 high-frequency phrases as search terms. Results show that Lingo-Word2Vec, STC-Word Net and bisecting K-means-Word2Vec have better clustering effects. In 5 points evaluation system, survey quality scores obtained by designing methods are close to 3, indicating surveys are within acceptable limits. When considering sentence location information, survey quality will be improved. Combination of Lingo, Word2Vec, TF-IDF or MMR can acquire higher survey quality.Research limitations: The manual evaluation method may have a certain subjectivity. We use a simple linear function to combine Word2Vec and Word Net that may not bring out their strengths. The generated surveys may not contain some newly created knowledge of some articles which may concentrate on sentences with no citing.Practical implications: CitationAS tool can automatically generate a comprehensive, detailed and accurate survey according to user’s search terms. It can also help researchers learn about research status in a certain field.Originality/value: Citaiton AS tool is of practicability. It merges cluster labels from semantic level to improve clustering results. The tool also considers sentence location information when calculating sentence score by TF-IDF and MMR. 展开更多
关键词 Automatic survey system Citation content Clustering algorithms Labelgeneration approaches Sentence extraction methods
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Mitochondrial dysfunction and quality control lie at the heart of subarachnoid hemorrhage 被引量:5
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作者 Jiatong Zhang Qi Zhu +4 位作者 jie wang Zheng Peng Zong Zhuang Chunhua Hang Wei Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期825-832,共8页
The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood flow.Mitochondria are directly affected by direct facto... The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood flow.Mitochondria are directly affected by direct factors such as ischemia,hypoxia,excitotoxicity,and toxicity of free hemoglobin and its degradation products,which trigger mitochondrial dysfunction.Dysfunctional mitochondria release large amounts of reactive oxygen species,inflammatory mediators,and apoptotic proteins that activate apoptotic pathways,further damaging cells.In response to this array of damage,cells have adopted multiple mitochondrial quality control mechanisms through evolution,including mitochondrial protein quality control,mitochondrial dynamics,mitophagy,mitochondrial biogenesis,and intercellular mitochondrial transfer,to maintain mitochondrial homeostasis under pathological conditions.Specific interventions targeting mitochondrial quality control mechanisms have emerged as promising therapeutic strategies for subarachnoid hemorrhage.This review provides an overview of recent research advances in mitochondrial pathophysiological processes after subarachnoid hemorrhage,particularly mitochondrial quality control mechanisms.It also presents potential therapeutic strategies to target mitochondrial quality control in subarachnoid hemorrhage. 展开更多
关键词 mitochondrial biogenesis mitochondrial dynamics mitochondrial dysfunction mitochondrial fission and fusion mitochondrial quality control MITOPHAGY subarachnoid hemorrhage
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Brain-wide activation involved in 15 mA transcranial alternating current stimulation in patients with first-episode major depressive disorder 被引量:2
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作者 jie wang Wenfeng Zhao +8 位作者 Huang wang Haixia Leng Qing Xue Mao Peng Baoquan Min Xiukun Jin Liucen Tan Keming Gao Hongxing wang 《General Psychiatry》 CSCD 2024年第2期265-273,共9页
Background Although 15 mA transcranial alternating current stimulation(tACS)has a therapeutic effect on depression,the activations of brain structures in humans accounting for this tACS configuration remain largely un... Background Although 15 mA transcranial alternating current stimulation(tACS)has a therapeutic effect on depression,the activations of brain structures in humans accounting for this tACS configuration remain largely unknown.Aims To investigate which intracranial brain structures are engaged in the tACS at 77.5 Hz and 15 mA,delivered via the forehead and the mastoid electrodes in the human brain.Methods Actual human head models were built using the magnetic resonance imagings of eight outpatient volunteers with drug-naïve,first-episode major depressive disorder and then used to perform the electric field distributions with SimNIBS software.Results The electric field distributions of the sagittal,coronal and axial planes showed that the bilateral frontal lobes,bilateral temporal lobes,hippocampus,cingulate,hypothalamus,thalamus,amygdala,cerebellum and brainstem were visibly stimulated by the 15 mA tACS procedure.Conclusions Brain-wide activation,including the cortex,subcortical structures,cerebellum and brainstem,is involved in the 15 mA tACS intervention for first-episode major depressive disorder.Our results indicate that the simultaneous involvement of multiple brain regions is a possible mechanism for its effectiveness in reducing depressive symptoms. 展开更多
关键词 STIMULATION INVOLVEMENT ACTIVATION
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Substitutions of stem-loop subdomains in internal ribosome entry site of Senecavirus A:Impacts on rescue of sequence-modifying viruses 被引量:1
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作者 Qianqian wang jie wang +5 位作者 Lei Zhang Xiaoxiao Duan Lijie Zhu Youming Zhang Yan Li Fuxiao Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2391-2406,共16页
Senecavirus A(SVA)has a positive-sense,single-stranded RNA genome.Its 5´untranslated region harbors an internal ribosome entry site(IRES),comprising 10 larger or smaller stem-loop structures(including a pseudokno... Senecavirus A(SVA)has a positive-sense,single-stranded RNA genome.Its 5´untranslated region harbors an internal ribosome entry site(IRES),comprising 10 larger or smaller stem-loop structures(including a pseudoknot)that have been demonstrated to be well conserved.However,it is still unclear whether each stem-loop subdomain,such as a single stem or loop,is also highly conserved.To clarify this issue in the present study,a set of 29 SVA cDNA clones were constructed by site-directed mutagenesis(SDM)on the IRES.The SDM-modified scenarios included:(1)stem-formed complementary sequences exchanging with each other;(2)loop transversion;(3)loop transition;and(4)point mutations.All cDNA clones were separately transfected into cells for rescuing viable viruses,whereas only four SVAs of interest could be recovered,and were genetically stable during 20 passages.One progeny grew significantly slower than the other three did.The dual-luciferase reporter assay showed that none of the SDM-modified IRESes significantly inhibited the IRES activity.Our previous study indicated that a single motif from any of the ten stem structures,if completely mutated,would cause the failure of virus recovery.Interestingly,our present study revealed three stem structures,whose individual complementary sequences could exchange with each other to rescue sequence-modifying SVAs.Moreover,one apical loop was demonstrated to have the ability to tolerate its own full-length transition,also having no impact on the recovery of sequence-modifying SVA.The present study suggested that not every stem-loop structure was strictly conserved in its conformation,while the full-length IRES itself was well conserved.This provides a new research direction on interaction between the IRES and many factors. 展开更多
关键词 SVA HCV IRES HCV-like IRES stem-loop structure cDNA clone virus rescue mutation
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调控Ru的电子态以促进乙烯在酸中高选择性电氧化合成乙二醇
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作者 王杰 陈怡和 +4 位作者 王宇达 赵浩 叶进裕 程庆庆 杨辉 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第5期376-385,共10页
乙二醇(EG)是一种重要的化工产品,由于在化学品制造行业的广泛应用而备受关注.然而,目前工业上制备乙二醇主要采用乙烯作为原料,经过环氧化和水解两步反应,这一过程不仅需要高温高压,还需使用成本高的氧化剂(如H_(2)O_(2)),这违背了绿... 乙二醇(EG)是一种重要的化工产品,由于在化学品制造行业的广泛应用而备受关注.然而,目前工业上制备乙二醇主要采用乙烯作为原料,经过环氧化和水解两步反应,这一过程不仅需要高温高压,还需使用成本高的氧化剂(如H_(2)O_(2)),这违背了绿色化学的原则.因此,电催化阳极氧化作为一种新兴的合成策略,正逐渐受到研究者的青睐.该技术仅通过电子转移并利用水作为氧源,就能够高效合成高附加值含氧化学品.特别是,阳极氧化反应可与阴极还原反应(例如氢析出反应)相耦合,实现能量的高效利用.尽管电催化阳极氧化具有诸多优势,但目前在乙烯电氧化合成乙二醇过程中,其选择性仍然较低,这导致后续的纯化过程变得复杂且成本高昂.因此,开发高选择性的电氧化合成乙二醇技术,成为了一项迫切且极具挑战性的任务.本文提出了一种Ir和Ru合金化策略,以提高乙烯电氧化制备乙二醇的选择性和耐久性.研究结果表明,当Ir和Ru的原子比达到适当的比例(即Ir_(0.54)Ru_(0.46))时,所制备的IrRu合金表现出近100%的乙二醇选择性,远远优于Ru NPs对照组样品(43.8%).此外,在1.475 V的电压下,Ir_(0.54)Ru_(0.46)催化生成乙二醇产率达到了60.62 mmolgRu^(-1) h^(-1),是Ru NPs上最高产率(21.75 mmolgRu^(-1) h^(-1))的2.8倍.在耐久性测试中,Ir_(0.54)Ru_(0.46)能够稳定催化生成乙二醇超过12 h,其生成速率为6μmol L^(-1) h^(-1).相比之下,对照组样品Ru NPs在电解反应3 h后已失去活性.能量损失谱分析显示,Ir_(0.54)Ru_(0.46)在电解2 h后形成了稳定的表面富Ir核壳结构IrRu@Ir,这是催化剂稳定性提升的关键.先进光谱研究进一步揭示,Ir的引入导致了电子由Ru位点向Ir流动,使Ru位点带正电荷,从而减弱了OH的吸附.OH脱附实验结果表明,随着Ir/Ru原子比的增加,OH更容易从Ru位点脱附,这促进了OH与乙烯的偶联反应.自由基淬灭和氘代同位素标记实验结果表明,在IrRu催化剂上,乙烯到乙二醇的转化并非级联反应,而是直接的表面催化反应,其中OH的转移是决速步骤.X射线光电子能谱分析显示,随着合金中Ir比例的增加,合金d带中心下移,这有利于关键中间体(*OH等)的转移.原位红外光谱表明,乙烯分子在Ru位点上通过Pauling型吸附构型被活化.值得注意的是,仅检测到*CH_(2)CH_(2)OH中间体,而未检测到其他氧基团(如羰基),这表明在反应过程中没有发生过氧化现象.密度泛函理论计算进一步证实,与Ir合金化不仅加速了OH的转移,还优化了反应途径,使乙二醇的选择性达到100%.综上,本文设计了不同Ir/Ru原子比的IrRu合金催化剂,通过有效调控活性位点Ru的电子结构,优化了OH的结合能,使乙烯可以100%选择性高效转化为乙二醇,这为开发高选择性电催化剂用于乙二醇电合成提供了新思路. 展开更多
关键词 乙烯电氧化 电合成乙二醇 高选择性 IrRu合金 电子结构
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Exploring cerebral structural and functional abnormalities in a mouse model of post-traumatic headache induced by mild traumatic brain injury 被引量:1
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作者 Dan Yang Bin-Bin Nie +6 位作者 Jin-Gang He Zong-Qiang Lv Feng-Feng Mo Si-Yi Ouyang jie wang Ju-Xiang Chen Tao Tao 《Zoological Research》 SCIE CSCD 2024年第3期648-662,共15页
Mild traumatic brain injury(mTBI)-induced post-traumatic headache(PTH)is a pressing public health concern and leading cause of disability worldwide.Although PTH is often accompanied by neurological disorders,the exact... Mild traumatic brain injury(mTBI)-induced post-traumatic headache(PTH)is a pressing public health concern and leading cause of disability worldwide.Although PTH is often accompanied by neurological disorders,the exact underlying mechanism remains largely unknown.Identifying potential biomarkers may prompt the diagnosis and development of effective treatments for mTBI-induced PTH.In this study,a mouse model of mTBI-induced PTH was established to investigate its effects on cerebral structure and function during short-term recovery.Results indicated that mice with mTBI-induced PTH exhibited balance deficits during the early post-injury stage.Metabolic kinetics revealed that variations in neurotransmitters were most prominent in the cerebellum,temporal lobe/cortex,and hippocampal regions during the early stages of PTH.Additionally,variations in brain functional activities and connectivity were further detected in the early stage of PTH,particularly in the cerebellum and temporal cortex,suggesting that these regions play central roles in the mechanism underlying PTH.Moreover,our results suggested that GABA and glutamate may serve as potential diagnostic or prognostic biomarkers for PTH.Future studies should explore the specific neural circuits involved in the regulation of PTH by the cerebellum and temporal cortex,with these two regions potentially utilized as targets for non-invasive stimulation in future clinical treatment. 展开更多
关键词 Post-traumatic headache(PTH) Mild traumatic brain injury(mTBI) Metabolic kinetics FMRI CEREBELLUM
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Review of artificial intelligence applications in astronomical data processing 被引量:2
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作者 Hailong Zhang jie wang +3 位作者 Yazhou Zhang Xu Du Han Wu Ting Zhang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期1-15,共15页
Artificial Intelligence(AI)is an interdisciplinary research field with widespread applications.It aims at developing theoretical,methodological,technological,and applied systems that simulate,enhance,and assist human ... Artificial Intelligence(AI)is an interdisciplinary research field with widespread applications.It aims at developing theoretical,methodological,technological,and applied systems that simulate,enhance,and assist human intelligence.Recently,notable accomplishments of artificial intelligence technology have been achieved in astronomical data processing,establishing this technology as central to numerous astronomical research areas such as radio astronomy,stellar and galactic(Milky Way)studies,exoplanets surveys,cosmology,and solar physics.This article systematically reviews representative applications of artificial intelligence technology to astronomical data processing,with comprehensive description of specific cases:pulsar candidate identification,fast radio burst detection,gravitational wave detection,spectral classification,and radio frequency interference mitigation.Furthermore,it discusses possible future applications to provide perspectives for astronomical research in the artificial intelligence era. 展开更多
关键词 Astronomical techniques Astronomical methods Astroinformatics
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Au NPs/Cu-TCPP材料的构筑及其催化薄荷醇氧化的研究
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作者 李世叶 张剑 +3 位作者 王杰 杨超 张晋 成世兴 《日用化学工业(中英文)》 CAS 北大核心 2024年第11期1330-1338,共9页
二维纳米片具有大的比表面积和高孔隙率的特征,这使得其可以承载更多的活性中心,从而提高该材料的催化性能。如Cu-TCPP纳米片,拥有大的比表面积,可用于负载Pd NPs、Pt NPs以及Au NPs,以获得X NPs/Cu-TCPP纳米片(X=Pd NPs、Pt NPs和Au N... 二维纳米片具有大的比表面积和高孔隙率的特征,这使得其可以承载更多的活性中心,从而提高该材料的催化性能。如Cu-TCPP纳米片,拥有大的比表面积,可用于负载Pd NPs、Pt NPs以及Au NPs,以获得X NPs/Cu-TCPP纳米片(X=Pd NPs、Pt NPs和Au NPs)。本研究首先通过水热法,以三水合硝酸铜(Cu(NO_(3))_(2)·3H_(2)O)为金属盐,4-羧基卟啉(TCPP)为有机配体,N,N-二甲基甲酰胺(DMF)和CH_(3)CH_(2)OH(体积比3∶1)的混合溶液作为溶剂,合成Cu-TCPP纳米片。随后,采用还原法将Au NPs负载到Cu-TCPP纳米片上,形成Au NPs/Cu-TCPP纳米片,用于催化薄荷醇进行选择性氧化反应。在反应中,以叔丁基过氧化氢(TBHP)为氧化剂,乙腈(Me CN)为溶剂,氨基酸咪唑离子液体([C_(4)mim]Cys)为助催化剂,Au NPs/Cu-TCPP催化薄荷醇进行选择性氧化,生成薄荷酮。在50℃下反应18 h,薄荷醇的转化率和薄荷酮的选择性和产率都达到最高,分别为70.2%,99.9%和69.5%,该方法不仅将薄荷醇转化为高选择性的薄荷酮,而且操作简便,绿色环保,符合当前绿色化工发展的要求。 展开更多
关键词 二维纳米片 Au NPs/Cu-TCPP纳米片 薄荷醇 选择性氧化 薄荷酮
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A deep learning model based on contrast-enhanced computed tomography for differential diagnosis of gallbladder carcinoma 被引量:1
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作者 Fei Xiang Qing-Tao Meng +4 位作者 Jing-Jing Deng jie wang Xiao-Yuan Liang Xing-Yu Liu Sheng Yan 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第4期376-384,共9页
Background:Gallbladder carcinoma(GBC)is highly malignant,and its early diagnosis remains difficult.This study aimed to develop a deep learning model based on contrast-enhanced computed tomography(CT)images to assist r... Background:Gallbladder carcinoma(GBC)is highly malignant,and its early diagnosis remains difficult.This study aimed to develop a deep learning model based on contrast-enhanced computed tomography(CT)images to assist radiologists in identifying GBC.Methods:We retrospectively enrolled 278 patients with gallbladder lesions(>10 mm)who underwent contrast-enhanced CT and cholecystectomy and divided them into the training(n=194)and validation(n=84)datasets.The deep learning model was developed based on ResNet50 network.Radiomics and clinical models were built based on support vector machine(SVM)method.We comprehensively compared the performance of deep learning,radiomics,clinical models,and three radiologists.Results:Three radiomics features including LoG_3.0 gray-level size zone matrix zone variance,HHL firstorder kurtosis,and LHL gray-level co-occurrence matrix dependence variance were significantly different between benign gallbladder lesions and GBC,and were selected for developing radiomics model.Multivariate regression analysis revealed that age≥65 years[odds ratios(OR)=4.4,95%confidence interval(CI):2.1-9.1,P<0.001],lesion size(OR=2.6,95%CI:1.6-4.1,P<0.001),and CA-19-9>37 U/mL(OR=4.0,95%CI:1.6-10.0,P=0.003)were significant clinical risk factors of GBC.The deep learning model achieved the area under the receiver operating characteristic curve(AUC)values of 0.864(95%CI:0.814-0.915)and 0.857(95%CI:0.773-0.942)in the training and validation datasets,which were comparable with radiomics,clinical models and three radiologists.The sensitivity of deep learning model was the highest both in the training[90%(95%CI:82%-96%)]and validation[85%(95%CI:68%-95%)]datasets.Conclusions:The deep learning model may be a useful tool for radiologists to distinguish between GBC and benign gallbladder lesions. 展开更多
关键词 Gallbladder carcinoma Computed tomography Deep learning Radiomics
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铜-焦脱镁叶绿酸a甲酯的合成及抗肿瘤活性研究实验教学设计
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作者 宋平 张楠 +3 位作者 王洁 闫蕊 王志强 金英学 《大学化学》 CAS 2024年第6期278-286,共9页
本实验设计合成了铜-焦脱镁叶绿酸a甲酯(Cu-MPPa),用于活性氧(ROS)介导的癌症治疗和消耗谷胱甘肽,并通过类Fenton反应循环产氧维持细胞内高浓度氧。实验过程中考察了Cu-MPPa的活性氧产生能力、氧气产生能力和谷胱甘肽消耗能力等性能。... 本实验设计合成了铜-焦脱镁叶绿酸a甲酯(Cu-MPPa),用于活性氧(ROS)介导的癌症治疗和消耗谷胱甘肽,并通过类Fenton反应循环产氧维持细胞内高浓度氧。实验过程中考察了Cu-MPPa的活性氧产生能力、氧气产生能力和谷胱甘肽消耗能力等性能。所合成中间体的结构用质谱进行了表征。这个实验综合了有机化学合成、仪器分析化学和生物化学实验,要求由三名学生组成实验小组,大约需要24学时,旨在培养学生综合创新能力、解决复杂问题能力和培养团队合作精神。 展开更多
关键词 铜-焦脱镁叶绿酸a甲酯 活性氧 有机化学合成 仪器分析 抗肿瘤
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数字浪潮中的文化引擎:电子游戏与中华文化全球传播
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作者 马骁 王杰 张雪 《新媒体与社会》 2024年第4期351-361,427,共12页
电子游戏成为数字时代中华文化破圈出海的新引擎。本文从媒介文化学视角深入探讨了电子游戏在中华文化全球传播中的在地实践、显著优势以及提升路径。研究发现:电子游戏通过精心的内容选择、创新的形式表现和广泛的传播途径,向世界展示... 电子游戏成为数字时代中华文化破圈出海的新引擎。本文从媒介文化学视角深入探讨了电子游戏在中华文化全球传播中的在地实践、显著优势以及提升路径。研究发现:电子游戏通过精心的内容选择、创新的形式表现和广泛的传播途径,向世界展示了中华文化的深厚底蕴,但也面临着表达浅层化、意蕴折扣化、渠道单一化和目标倒置化等问题。亟须在文化内涵、技术赋能、品质提升、文化引导和国际合作等层面完善电子游戏传播中华文化的实践路径,向世界展示中华文明的独特魅力。 展开更多
关键词 文化引擎 电子游戏 中华文化 全球传播
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Design and additive manufacturing of bionic hybrid structure inspired by cuttlebone to achieve superior mechanical properties and shape memory function
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作者 Luhao Yuan Dongdong Gu +8 位作者 Xin Liu Keyu Shi Kaijie Lin He Liu Han Zhang Donghua Dai Jianfeng Sun Wenxin Chen jie wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第5期189-206,共18页
Lightweight porous materials with high load-bearing,damage tolerance and energy absorption(EA)as well as intelligence of shape recovery after material deformation are beneficial and critical for many applications,e.g.... Lightweight porous materials with high load-bearing,damage tolerance and energy absorption(EA)as well as intelligence of shape recovery after material deformation are beneficial and critical for many applications,e.g.aerospace,automobiles,electronics,etc.Cuttlebone produced in the cuttlefish has evolved vertical walls with the optimal corrugation gradient,enabling stress homogenization,significant load bearing,and damage tolerance to protect the organism from high external pressures in the deep sea.This work illustrated that the complex hybrid wave shape in cuttlebone walls,becoming more tortuous from bottom to top,creates a lightweight,load-bearing structure with progressive failure.By mimicking the cuttlebone,a novel bionic hybrid structure(BHS)was proposed,and as a comparison,a regular corrugated structure and a straight wall structure were designed.Three types of designed structures have been successfully manufactured by laser powder bed fusion(LPBF)with NiTi powder.The LPBF-processed BHS exhibited a total porosity of 0.042% and a good dimensional accuracy with a peak deviation of 17.4μm.Microstructural analysis indicated that the LPBF-processed BHS had a strong(001)crystallographic orientation and an average size of 9.85μm.Mechanical analysis revealed the LPBF-processed BHS could withstand over 25000 times its weight without significant deformation and had the highest specific EA value(5.32 J·g^(−1))due to the absence of stress concentration and progressive wall failure during compression.Cyclic compression testing showed that LPBF-processed BHS possessed superior viscoelastic and elasticity energy dissipation capacity.Importantly,the uniform reversible phase transition from martensite to austenite in the walls enables the structure to largely recover its pre-deformation shape when heated(over 99% recovery rate).These design strategies can serve as valuable references for the development of intelligent components that possess high mechanical efficiency and shape memory capabilities. 展开更多
关键词 additive manufacturing laser powder bed fusion bionic structure CUTTLEBONE mechanical properties shape memory function
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